VOL. XIX, PP. 183-192 DECEMBER 8, 1906 
PROCEEDINGS 
OF THE 
BIOLOGICAL SOCIETY OF WASHINGTON 
NOTES ON GENERA OF PANICEAE. I. 
BY AGNES CHASE. 
One of the chief distinguishing characters of this tribe of 
grasses is the single fruit, composed of the more or less indurated 
lemma and palea, the latter firmly clasped by the margins of 
the lemma (rarely loose, as in Leptocoryphium and Hymenachne) , 
enclosing the free grain. This simple arrangement is variously 
modified in the different genera. After several years' study of 
the fruits of this tribe the writer proposes to offer this and sub 
sequent papers on the genera with special reference to the fruits, 
figuring and describing the fruit of the type species of each genus. 
It may be well to state why the character of the fruit is held 
to have superior generic value. It is because: 1. The character 
of the fruit is constant in the same species. The first glume 
may be present or obsolete in Paspalum distichum L., P. Drum- 
mQndiiV&sey, P. bifidum (Bertol.) Nash, and in a few others, not 
only in the same species but in the same specimen, but within 
are always the same plano-convex, chartaceous-indurated fruits, 
the lemma with inrolled margins, the palea included at the 
apex as well as on the margins; Reimaria oligostachya Munro 
may lack but one instead of both glumes but the fruit remains 
constant; Echinochloa crus-galli (L.) Beauv. may have very long 
awns or be mucronate only, but the fruit will have the charac 
teristic abruptly acuminate apex, the palea free at the summit. 
2. The fruit with but slight modifications is constant for greater 
or smaller groups of similar species; that is, taking the fruit as 
a generic character it assembles species which show other resem 
blances, and does not arbitrarily assemble those which show no 
close affinity, as does the character of the presence of the first 
glume in Paspalum, which places in Dimorphostachys, founded 
on Paspalum monostachyum H. B. K., such diverse species as 
P. Drummondii Vasey and P. Schaffneri Fourn., when both have 
34 PROC. BIOL. Soc. WASH., VOL. XIX, 1906. (183) 
JSS" 5 " 1 ^^ 
ZQiW? 
184 Chase Notes on Genera of Paniceae. I. 
nearer relatives left in the genus Paspalum. The foregoing does 
not mean that the fruit is held to be the only generic character 
but merely that it is a strong one which has not received the 
attention it deserves ; while it is held that any generic character 
must be constant in a species and assemble species having other 
affinities. Such a character is the reversed position of the 
spikelets in Axonopus Beauv. (Anastrophus Schlecht.). The 
fruits alone would not separate this genus from Paspalum, but 
not one of the many specimens of the several species examined 
shows a spikelet placed otherwise than with the back of the fruit 
turned from the rachis. 
These studies are based on the material in the National Herba 
rium where all the genera of this tribe are represented, most of 
them by a large series of specimens. The figures* and descrip 
tions are drawn from mature or nearly mature fruits; since the 
spikelets fall at maturity it is difficult to find perfectly ripe fruit 
in herbarium specimens. 
The present paper is confined to that group of Paniceae in which 
the fruits are cartilaginous-indurated (not rigid) papillose, and 
usually dark colored; lemmas and paleas alike in texture, the 
lemmas with more or less prominent, white, hyaline margins not 
inrolled . 
KEY. 
Lemma boat-shaped, margin narrow Anthaenantia 
Lemma convex only. 
Palea not inclosed above, lemma hyaline at the summit. Leptocoryphium 
Palea inclosed, lemma with broad hyaline margin nearly 
to the base. 
Fruit lanceolate-acuminate, second glume and sterile 
lemma clothed with long hairs exceeding the 
spikelet, grain unequally biconvex Valota 
Fruit elliptic ; second glume and sterile lemma clothed 
with short hairs or nearly glabrous, grain plano 
convex in section. 
Spikelets disposed in 1-sided racemes which are 
digitate or racemose Syntlierisma 
Spikelets in panicles divergent at maturity .... Leptoloma 
GKNUS ANTHAENANTIA Beauv. 1812. Agros. 48. t. 10. f. 7. 
Axis paniculatus: Panicula subsimplex. Glumse subaequales, concave, 
herbaceae. FLOSC. INFER, neut. : Palese membranaceae, oppositse, rleis 
* The figures are all magnified 20 diameters. 
Chase Notes on Genera of Paniceae. I. 185 
hermaphrodites contrarie dispositse.FLOsc. SUPER, hermaph. : Paleae sub- 
car ti lag ineae. SPEC. Phalaris villosa MICH. 
Phalaris f villosa Michx. 1803. Fl. Bor. Am. 1 : 43. " HAB. in sylvis sab- 
ulosis Carolina." 
Just what is meant by the paleae of the neuter floret placed contrariwise 
to those of the perfect floret it is difficult to decide. The figure shows such 
an empty floret consisting of a small lemma and palea placed laterally 
against the palea of the fruit. Kunth (Rev. Gram. 1 : 217) reducing the 
genus to Panicum with the specific name of ignoratum, remarks that 
" Beauvois who never soaked the spikelets before examining them nor 
used a needle to open them " mistook the torn margins of the sterile lemma 
for a 2-valved floret. 
Anlaxanthus Ell. 1816. Bot. S. C. & Ga. 1 : 102. 
"Flores paniculati. Calyx 2-valvis, 1-floris ; valvis sequalibus, sulcatis 
Corolla 2-valvis, subaequalis." 
,/" Two species, A. cilialus and rufas are described, and 
"Phalaris villosa? Michx." is given under the first. 
Though the generic description says the spikelets are 
1-flowered, under ciliatus is stated : " at the back of the 
interior valve occurs a neutral floret, 1-valved, ovate, 
2-cleft, green." 
Aulaxia Nutt. 1818. Gen. 1 : 47. Description is nearly 
identical with that of Elliott, " 1-flowered, with the rudi 
ment of a second " added ; Aulaxanthus is given as 
synonym ; no reason is assigned for changing the name. 
These three generic names are founded on the same 
species. 
Description. Spikelets in narrow panicles, obovoid, 
first glume obsolete, second glume and sterile lemma 
subequal,very broad, with 5 strong nerves, the very thin 
internerves deeply folded and densely clothed with 
long hairs, the sterile lemma enclosing a small palea 
and sometimes a staminate flower ; fruit as long as the 
glume, plano-convex, subacute, chestnut brown, the lemma boat-shaped, 
the 3 nerves visible ; the white or pale margins very narrow ; palea en 
folded its entire length, the 2 nerves visible ; grain in section plano-convex. 
GENUS LEPTOCORYPHIUM NEES. 1829. AGROS. BRAS. 83. 
Calj ? x uniglumis, biflorus, gluma inferiore, deficiente. Flosculus inferior 
neuter, uniglumis * * * Flosculus superior hermaphoditus, calycis 
longitudine, in fructu persistens chartaceus (nee induratus), valvulis atten- 
uatis apice membranaceo-hyalinis lacero-ciliatis. [Whence the name 
from " \e7rr6s tennis et Kopv<t>Tj apex"] 
The first species under this genus is L. lanatum ( H. B. K. ) Nees, based on 
Paspalum lanatum H. B. K. 1815. Gen. PI. et Sp. 1 : 94. t. 29. " Crescit 
in regno Mexicano prope Venta del Cameron et Alto del Peregrino." 
Roemer & Schultes (1817. Syst. Veg. 2 : 322) transfer this species to 
Milium, in which disposition of it they are followed by Kunth (1829. Rev. 
186 
Chase Notes on Genera of Paniceae. I. 
Gram. 497), and Trinius (1834. Mem. Acad. St. Petersb. VI. 3 2 : 121). 
Bentham (1881. Journ. Linn. Soc. Bot. 19 : 39) transfers it to Auihaenantht 
stating: " From these [N. Am. Anthaenantia] I can not separategenerically 
the South American Leptocoryphiuin Nees, which be 
sides some slight specific characters only differs from 
the North American species in the second glume being 
constantly, instead of occasionally only, empty." Hems- 
ley (1885. Biol. Cent. Am. Bot. 3 : 483) follows Bentham ; 
Founder (1881. Mex. PI. 2: 13) upholds Lcplocoryphiuni, 
Description. Spikelets in narrow panicles, lanceolate; 
first glume obsolete; second glume and sterile lemma 
3 and 5 nerved, the internerves, which are not broad 
and infolded (or plaited) as in Anthaennlia, each with 
a row of long coarse hairs arising from tubercles (the 
tubercles sometimes obscure), the second glume shorter 
than the sterile lemma which equals the fruit and 
which is empty; fertile lemma slightly cartilaginous- 
indurated, minutely papillose (the papillae finer than 
in any of the other genera), chestnut with a white, 
delicately hyaline, summit, lacerate and often sparingly 
ciliate, a narrow hyaline margin extending down the 
sides to about the middle ; on the back near the base 
is a small impressed area thin and white ; palea with summit and margins 
like those of the lemma, not enclosed above, the 2 nerves obscurely visible ; 
grain oblong-elliptic, in section plano-convex. 
As shown by the fruit this seems to be, as Nees considered it, most nearly 
allied to Valotn (Trichachne Nees) from which he separated it chiefly on 
the absence of the first glume. The inflorescence is like that of Anthae- 
nantia, which it resembles also in lacking the first glume, but differs from 
in lacking the neuter palea or staminate flower and in the convex, not 
boat-shaped, lemma with a broad hyaline summit. It differs from both 
Valota and Anthaenantia in the fruit open at maturity. (A large number 
of specimens were examined and none in or past bloom were found closed.) 
Since this species fits so poorly in any other genus it seems wisest to main 
tain the one Nees established for it. Nees' single other species of Leplo- 
coryphium \ve have not seen. 
GENUS VALOTA ADANS. 1763. FAM. PL. 2:495. 
Gramen. Avenae. Sloan, t. 14. f. 2. Couronne de la gaine des feuilles : 
Membrane mediocre. Fleurs: Panicule etagee. Calice : Ovoide, sans 
aretes, a 3 bales velues. Corolle: Sans aretes. 
The reference to Sloane serves to identify the genus, which the very in 
sufficient description would not do, and fixes its identity with Andropugon 
insutare L. 
Andropogon insulare L. 1759. Pugill. Jam. 30; and Sp. PI. Ed. 2. 1763. 
2 : 1480. In the Pugillus no citation is given ; in the Species Plantarum 
Chase Notes on Genera of Paniceae. I. 187 
the previous publication by Linnaeus is cited, and also Brown Jam. 365, 
and Sloane, 1 : 43. t. 14. f. 2. " Hab. in Jamaica." 
Brown (1. c.) after his polynomial cites Sloane t. 14. 
Sloane's figure (1. c.) is an excellent representation of the upper portion 
of the plant, a leaf and overmature panicle. 
Panicum lanatum Rottb. 1776. Descr. PI. 3. Based on Andropogon insv- 
lare L.; the same reference to Sloane is also given. Here follows the first 
adequate description of the species, even the fruit being described : " Corol- 
Ise valcse 2 lanceolatse, concavse, acutissimse, membranacese." 
Milium villosum Sw. 1788. Prod. 24. Based on Andropogon insulare L. 
Beauvois 1812. Agros. 150, in the index refers Andropogon hmularis to 
Monachne, but this species is not mentioned under that genus on p. 49. 
Panicum leucophoeum H. B. K. 1815. Nov. Gen. et Sp. 1 : 97. Based on 
Andropogon insulare L. This species and P. adscendens H. B. K., which is 
Syntherisma sanguinalis or a close ally, are placed together under " 3) Spicis 
verticillatis, fasciculatis aut paniculatis (Digitarise plurimse)." 
Panicum insulare Meyer. 1818. Prim. Fl. Esseq. 60. Based on Andropogon 
insulare L. The " valves of the corolla " are given as coriaceous with mem- 
branaceous margins. 
Aci.carpa Raddi. 1823. Agros. Bras. 31. with one species A. sacchariflora 
Raddi 1. c. t. 1. f. 4. This is given on the authority of Nees. We have not 
seen the original publication. 
Trichachne Nees. 1829. Agros. Bras. 85. 
(a Qpl capilius et &x v ~n gluma.) 
Calyx bivalvis, subbiflorus, gluma inferiore minuta. Flosculus inferior 
univalvis vel bivalvis hirsutus, neuter; superior hermaphroditus, valvulis 
membranaceis mucronatis Caryopsis flosculi valvulis membranaceis vestita 
* * * Inflorescentia : racemi elongati, simplices, unilaterales, verticil- 
latim paniculati. Spiculae geminae ternaeve, altera brevius pedicellata. 
* * * Flosculus hermaphroditus # *- * bivalvis, glaber, mem- 
branaceus, valvulis lanceolatis in mucronum subulatum attenuatis ad 
fructum persistentibus membranaceo-chartaceis caryopsin tegentibus neque 
cum eadem induratis. * * * Differt a Panico praesertim gluma flosculi 
hermaphroditi, * * * at minime crustaceo seu cartilagineo indurato 
sed semper flexili. 
Acicarpa Raddi 1823. Agros. Bras. 31. t. 1. f. 4. is cited as synonym and 
a note of explanation added that the name is expunged because of its 
similarity to Acicarpha Juss. [1803]. Nees' first species is Trichachne insu- 
laris (L.) Nees, based on Andropogon insulare L. Five other species are 
included, T. sacchariflora (Raddi) Nees, and four new species from Brazil, 
T. recalva, tennis, velutina, and ferrnginea, the last two of which Nees says 
he saw in the Royal herbarium at Berlin. 
Grisebach (1864. Fl. Br. W. I. 557) places Panicum insulare and P. sac- 
charntum Buckl. in Trichotnena ; Stapf (1898, in Fl. Cap. 7 : 382) transfers 
" Panicum leucophaea Sw." to Digitaria, remarking, " the structure of the 
spikelets is * * * as in Digitarin." Stapf probably means P. leuco 
phoeum H, B. K. , which is a typonym of A . insulare L. Swartz did not pub 
lish the name given by Stapf. Millspaugh and Chase (1903, Fl. Yucatan, 
188 Chase Notes on Genera of Paniceae. I. 
Field Col. Mus. Bot. 3 : 23) transfer T. insularis to Syntherisma, remarking : 
" That this species belongs in the genus Syntherisma rather 
than in Panicum is shown chiefly by the fruiting glumes 
which are of the form characteristic of the former, having 
a floral glume with hyaline margins not inrolled." 
Description. Spikelets in pairs, short-pediceled in 2 rows 
along one side of a narrow rachis, the slender racemes 
erect or nearly so, solitary or fascicled along a common 
ax * s * rm i n a narrow panicle; spikelets lanceolate, first 
glume minute, glabrous, the second and sterile lemma us 
ually as long as the fruit or longer, 3-5 nerved, copiously 
clothed with long silky hairs (in one species, only, the 
silky hairs are not long and dense) ; fruit lanceolate, usual 
ly brown, the flat, white, hyaline margins broad; grain 
ellipsoid, in section unequally biconvex. 
This genus is very closely allied to Syntherisma Walt. 
One species, Panicum Pittieri Hack., has the inflorescence 
of Valota, but the hairs on the second glume and sterile 
lemma are not long and copious, and the second glume 
is shorter than the fertile lemma as in some Syntherismas. 
But considering the diverse aspect of the two genera as a whole it seems 
wisest to regard them as distinct. 
The following species are transferred to this genus : 
Valota insularis (L.) 
Andropogon insulare L. 1859. Pugill. Jam. 30. 
Valota saccharatum (Buckl.) 
Panicum lachnanthum Torr. 1856. Fac. Rail. Rep. 7 3 : 21, not Hochst. 
1855. 
Panicum saccharatum Buckl. 1866. Prel. Rep. Geol. & Agr. Surv. Tex. 
App. 2. " Middle Texas." 
Trichachne saccharatum (Buckl.) Nash. 1903 in Small Fl. So. U. S. 83. 
Valota Pittieri (Hack.) 
Panicum Pittieri Hack. 1901. Oest. Bot. Zeitsc. 51 : 367. " Costarica: in 
ripa rivi Rio Tirili prope San Jose leg. Tonduz: Pittierdistribuitsub 
nro. 6945." 
The species represented in American herbaria by Nealley's Texas collec 
tions and passing under the name Panicum tenerrimum Kunth, (based on 
Trichachne tennis Nees) does not well agree with Nees' description. Since 
authentic specimens of this and Nees' other Brazilian species have not yet 
been seen, his species and the Texas form are left for future study ; and to 
avoid the possibility of making unnecessary combinations by taking up 
possible synonyms these species and an Australian one with stramineous 
fruits are not here transferred to this genus. 
GENUS SYNTHERISMA WALT. 1788. FL. CAROL. 76. 
Digitaria Haller 1768. Stirp. Helv. 2 : 244 not Adans. 1763, nor Heist. 
1759, though Haller gives Heister and Adanson as authors of his Digitaria; 
but his description, though he evidently makes an effort to harmonize it 
Chase Notes on Genera of Paniceae. I. 189 
with those of Heister and Adanson by emphasizing the " excavations " of 
the rachis, applies not to Tripsacum but to the grasses so long known as 
Digitaria, and his pre-Linnaean references lead to P. sanguinale L. 
Antiquum nomen, & characteristicum, reddo plantis nostris, quse adeo 
vehementer a LINN.ENIS Panicis abludunt, nt nullo modo eo referripossint. 
Receptaculum Tritici, alternis scrobibus excavatum. Ad eas scrobes appli- 
cantur flosculi petiolati. Calyx biglumis, lineatus, altera gluma parva, 
mucronata, altera majori faciei floris respond ente, lineata: ita mucronata, 
compressa, ovato lanceolata uniflora, locusta oritur. Flos durus, nitens, 
siccus, convexus inde, hinc complanatus, & linea quasi divisus, non tamen 
penetrante. Nonquam satis potui distinguere divisionem in duas glumas. 
In cavea certe undique clausa semen sedet, compressum, planum. 
Under his first species, to which Haller, who evidently opposed such an 
innovation as a binomial system, applies a polynomial, " LINN. p. 84 " is 
cited, with Linnaeus' description of P. sanguinale used as a polynomial, the 
name sanguinale being omitted. The reference is to the 1762 edition of 
Species Plantarum. For discussion of Digitaria Heister see Hitchcock, Bot. 
Gaz. 38 : 298, and Nash, Bui. Torr. Bot. Club 25 : 289. 
Panicum sanguinale L. 1753. Sp. PI. 57. " Spicis aggregatis, basi interiore 
nodosis, flosculis geminis muticis, vaginis foliorum punctatis. * * * 
Habitat in America, Europe australi." 
The specimen under this name in the Linnaean herbarium is the tradi 
tional P. sanguinale fide Prof. A. S. Hitchcock who has seen it. The first 
reference after the description is to Royen Fl. Leyden 55, where, after the 
polynomial quoted by Linnaeus, Sloan. Hist. 1 : 113, t. 70, f. 3 is cited. The 
second reference is to Gron. Virg. 154 [error for 134]. Gronovius refers to 
Clayton n. 457. Linnaeus' reference (Sp. PI. 57) to Sloane 1 : 113 t. 70 f.2 
is evidently an error. The polynomial and figure cited in Royen applies 
to P. sanguinale. 
Syntherisma Walt. 1788. Fl. Carol. 76. 
CaL 1-florus, 2-valvis : valvulis planis, acutis interiore minore recta, 
exteriore lateribus corollam subamplexante. Cor. 2-valvis : valvulis mag- 
nitudine et figura valvulae majori calycis simillimis. * * * Semen 
unicum, calyce corollaque persistentibus vestitum. 
The first species is S. pr&cox Walt. "No specimen in [Walter's] her 
barium. There is not much doubt but this refers to Panicum sanguinale L. 
(Digitaria sariguinalis), as stated by Elliott and Michaux." Hitchcock, Six 
teenth Ann. Rept. Mo. Bot. Gard. 44. 
Michaux (1803. Fl. Bor. Am. 1 : 45) includes Syntherisma praecox Walt, 
as synonym under Digitaria sanguinalis Scop. 
This group has been held to be a genus or reduced to a section of Pani 
cum according, seemingly, to the weight given its form of inflorescence. 
Nees, while noting the less indurated and "always pliable" lemma of 
Trichachne, 'does not seem to have noted that the same is true of the group 
he placed as section Digitariae of Panicum, nor that the differences from 
Panicum which he points out for Trichachne do not separate that genus from 
his section Digitariae. The form of inflorescence does not clearly distinguish 
this genus from Panicum, since the species known as Panicum Perrolteti 
190 Chase Notes on Genera of Paniceae. I. 
Kunth (Paspalum Perrolteti Hook f.) and its close allies have sparingly 
branched racemes more or less naked at the base forming a panicle not 
greatly unlike that of Panicum proliferum and yet are true Syntherismas as 
shown by the spikelets and especially by the cartilaginous-papillose lemma 
with flat, hyaline margins. Hooker f. (1896 Fl. Br. Ind. 7 : 10) places 
these and other species of Section Digitaria in Paspalum, saying " As above 
defined, Paspalum includes the Digitaria section of Panicum, which appears 
to me to be artificially placed in the latter genus, because of the occasional 
presence of a very minute scale-like glume at the base of what is the 3rd 
gl. of Panicum (that opposite the flg.). This minute glume which is present 
or absent even in the same species, is nerveless and never embraces that 
above it, as the lowest glume always does* in Panicum proper." The first 
glume is not only present or absent in the same species in Syntherisma, but 
sometimes in the same specimens, as in those of P. Perrotteti in the National 
Herbarium. Nash (Bui. Torr. Bot. Club 25 : 289) while contending that 
Syntherisma is as worthy of generic rank as are Paspalum, 
Anthaenantia , Eriochloa, Isachne, Ichnanthus, and TricJio- 
laena fails to point out why it is so, and adds : " Our own 
view is that Syntherisma is more nearly related to Paspalum 
than to Panicum, and if its union with either genus were 
desirable it would certainly be with the former and not 
with the latter." If the cartilaginous-papillose lemma with 
flat hyaline margins be taken for the chief generic char 
acter, Syntherisma is at once clearly distinguished from 
both Panicum and Paspalum, with no intermediate species. 
Description. Spikelets solitary or in 2's or 3's, subsessile 
or short-pediceled, alternate in 2 rows on one side of a 
3-angled winged or wingless rachis, the slender racemes 
usually more or less spreading, usually digitate or in ap 
proximate fascicles at the summit of the culm, rarely dis 
tributed along the axis ; spikelets lanceolate or elliptic ; first glume minute 
or wanting, the second glume equalling the sterile lemma or shorter, fruit 
lanceolate or elliptic, the flat, hyaline margins white or pale; grain sub- 
elliptic, in section plano-convex or slightly concavo-convex. 
The affinities of Syntherisma, are with Valola on the one hand and An 
thaenantia on the other. To the former it is allied through V. Pittieri and 
the species mentioned above as " Panicum tenerrimum " from Texas. Syn 
therisma approaches Anthaenantia through Panicum ($ Digitaria) adustum 
Nees and Anthaenantia Hackeli Arech. allied species, and Panicum badium 
Scribn. & Merr., which are placed in Syntherisma rather than in Ardhae- 
nanlia on the following characters : Spikelets in pairs in 2 rows along one 
side of a triangular rachis ; a minute first glume present (though this has 
little weight) ; second glume not equalling the sterile lemma (which is 
empty or contains only a nerveless rudiment of a palea), neither of them 
broad with deeply folded internerves as in Anthaenantia; lemma not 
boat-shaped, the hyaline margins broad. In addition to the species con- 
* Hooker was probably not acquainted with the Dichotomous Panicums in which 
he first glume is often nerveless and seldom embraces the second. 
Chase Notes on Genera of Paniceae. I. 191 
sidered by Nash (1. c.) in his treatment of the genus the following are here 
transferred : 
Syntherisma adusta (Xees) 
Pnnicum aduxtum Nees. 1829. Agros. Bras. 101. "Habitat in Brasilia 
meridional!. (Sellow.)" 
Syntherisma badia (Scribn. & Merr.) 
Panicum (Syntherisma) badium Scribn. & Merr. 1901. U. S. Dept. Agr. Div- 
Agros. Bui. 24: 12. "Sierra de San Felipe, State of Oaxaca" 915 
C. L. Smith. 
Syntherisma Hackeli (Arech.) 
Anthaenantia HacMi Arech. 1894. Anal. Mus. Nac. Montevideo 2 : 96, t. 
5. Figueira, Uruguay. 
Syntherisma velutina (DC.) 
Milium velutinvm DC. 1813. Cat. Hort. Monsp. 12fi. " Hab. in Mexico." 
Patpalum? velutinum Kth. 1829. Rev. Gram. 1 : 27. 
Represented by Pringle 6628 and 9565. 
Syntherisma Perrotteti (Kth.) 
Panicum Perrotteti Kth. 1829. Rev. Gram. 2 : 395. t. 3. " Crescit in Sene- 
galia, prope Walo." 
Syntherisma stenotaphroides (Nees) 
Pmiicum ($ Digitaria) stenotaphroides Nees 1854 in Steud. Syn. PI. Glum. 
1 : 41. "Ins. Choin legit Cuming." 
This and an allied species are peculiar in having a thickened rachis, the 
solitary spikelets sunken in the alternate notches. 
Species as yet imperfectly understood are not here transferred. 
GENUS LEPTOLOMA GEN. NOV. 
Inflorescentia paniculata, paniculapauciflora, maturitatediffusa; spiculae 
1-florae, fusiformae, solitariae, aut raro per paria, in pedicellis tenuibus 
triangularibus ; gluma prima minuta aut deficiens, secunda 3-nervis ; lem 
ma neutrum 5-7 nerve ; fructus ellipticus, acutus ; lemma hermaphroditum 
cartilagineo-induratum, papillosum, marginibus delicatus hyalinas, planis; 
paleasimilis ; caryopsis oblongo-elliptica lemmate paleaque inclusa, libera. 
Gramina perennia, caespitosa, ramosa, culmis fragilibus, laminis planis, 
ligulis membranaceis. Maturitate paniculae se dissipant et pervolvunt 
Panico capillari similes. Nomen ab \7rr6s delicatus et Xw/xa margo. 
Inflorescence a few-flowered panicle diffuse at maturity ; 
spikelets 1-flowered, fusiform, solitary or rarely in 2's on slen 
der triangular pedicels ; first glume minute or obsolete, the 
second 3-nerved, nearly as long as the 5-7 nerved sterile 
lemma, a more or less prominent stripe of appressed silky 
hairs down the internodes and margins of each ; sterile lemma 
empty or enclosing a minute nerveless rudimentary palae ; 
fruit elliptic, acute, brown; fertile lemma cartilaginous-indu 
rated papillose, with delicate hyaline flat margins, enclosing 
a palea of the same texture : styles long and delicate, stigmas 
plumose, the branches more long and slender than in Panicum, 
rather less so than in Syntherisma; grain oblong-elliptic, in 
section plano-convex ; free within the closed lemma and palea . 
Tufted branching perennials with brittle culms, flat blades, 
192 Chase Notes on Genera of Panic eae. I. 
and membra naceous lignles. At maturity the panicles break away and 
roll like tumble-weeds. Name from Xe7rr6s delicate and AcD^a border in refer 
ence to the hyaline margins of the fertile lemma. 
Type. Panicum cognatum Schultes. 
Leptoloma cognata (Schultes.) 
Panicum divergrns Muhl. in Ell. 1816. Sk. Bot. 1 : 130. not H. B. K.1815. 
Specimen in Elliott herbarium in College of Charleston. 
Elliott gives " Muhl. Cat." without page as authority for this name ; in 
Muhl. Cat. 9 (1813) divergens is a nomen nudum. 
Panicum divergens Muhl. 1817. Gram. 120. " Habitat in Carolina." 
Specimen in the Muhlenberg herbarium in Philadelphia Academy of Nat 
ural Sciences, marked " Elliott 353." In the same folio with this is a 
specimen of Panicum Philadelphicum marked "M. 112b." 
Panicum cognatum Schultes 1824. Mant. 2 : 235. Muhlenberg's descrip 
tion is copied and P. divergens Muhl. is cited as synonym, the name 
changed, doubtless, because of P. divergens H. B. K., though this older use 
of the name is not mentioned. Thus it is the second publication of P. 
divergens Muh\. (that in Muhl. Gram.) on which Schultes bases his P. cog 
natum. Hence the specimen in Muhlenberg's herbarium is the type. 
Panicum autumn ale Bosc. Spreng. 1825. Syst. 1 : 320. 
This name as used by American authors is synonymous with above, but 
we have not seen Bosc's specimen. Sprengel (1. c.) places the description 
of P. autnmnale next to that of P. divergens Muhl. The brief description 
would apply to any Panicum with an effuse capillary panicle. It was not 
known to Sprengel where the specimen came from ; " Patria?" he adds to 
his description, and indicates he saw the specimen in the WiUdenow her 
barium. 
The sheaths and blades of this species, especially the lower ones, are 
often papillose pubescent, commonly so in Western specimens, though the 
type is almost glabrous. Pringle 489, Chihuahua, Mexico, represents an 
extreme form with slightly larger spikelets, having densely silky-pubescent 
internerves, which would appear to be a distinct species except for the 
fact that the inter-grades are more numerous than the extreme form. This 
is the only species of this genus known in the northern hemisphere. Three 
or four species are found in Australia. 
Leptoloma divaricatissima (R. Br.) 
Panicum divaricalissimum R. Br. 1810. Prod. 192. Port Jackson, New 
Holland. 
Leptoloma mac rate nium (Benth.) 
Panicum macratenium Benth. 1878. Fl. Australia 7 : 468. " Queensland, 
Rockhampton, O'Shanesy." 
Leptoloma coenicola (F. Muell.) 
Panicum coenicolum F. Muell. 1855 in Trans. Viet. Inst. 45. Cudnaka, 
S. Australia, F. Mueller. 
Panicum papposurn R. Br. Prod. 192, and P. nematostachyum Bailey 1903 
in Bot. Bui. Dept. Agr. Queensl. 16 : 2, of which we have not seen speci 
mens, probably belong here. The former is P. autumnale F. Muell. Fragm. 
8 : 196, not Bosc, fide Bentham Fl. Australia 7 : 469.