ANNALS OF THE MISSOURI BOTANICAL GARDEN CHROMOSOME NUMBER IN TWO CYTOLOGICALLY UNKNOWN NEW WORLD FAMILIES, TOVARIACEAE AND VIVIANIACEAE In a recent survey of cytology in relation to angiosperm phylogeny, Raven (1975) drew attention to the remaining gaps in the chromosome records for fam-ilies and taxonomically critical genera. A concerted effort has since been made by Raven and others to obtain cytological information for these taxa. This long-term project has yielded results for several groups and the two counts re-ported here represent the first records for two dicot families. Tovaria was counted from pollen mother cells, material being fixed in thewild by A. Gentry. Viviania was grown from seed provided by O. Z�llner andcounts were obtained from root tips. Root tips were treated as recently describedby Goldblatt & Endress (1977). VIVIANIACEAE Viviania crenata Hook. 2n = 14. Chile, Prov. Aconcagua, Resguardo LosPatos, 1200 m, Zollner 8316 (MO). The family is traditionally included in Geraniaceae but is recognized byseveral recent phylogenists, including Hutchinson (1959), Takhtajan (1969), andDahlgren (1975). As revised by Lefor (1975), it comprises four genera, ail ofsouthern South America. Vivianiaceae has been associated with several familiesapart from Geraniaceae, most notably Caryophyllaceae (Centrospermae) (Bor-tenschlager, 1967; Takhtajan, 1973) and Polemoniaceae (Lefor, 1971). Behnke& Mabry (1977) have shown quite conclusively on chemical and ultrastructuralgrounds that Vivianiaceae is not related to Centrospermae. A relationship withPolemoniaceae has received little support so that on balance, there seems everyreason for treating Vivianiaceae in Geraniales, either as a separate family or inGeraniaceae. Chromosome number of n = 7 in Viviania crenata accords with either place-ment, though not ruling out other treatments. Geraniaceae (sensu stricto) hashigh base numbers in ail genera, with a range x = 14 through x = 10. Tropaeola-ceae has x = 14, 13, 12, while lower base numbers are characteristic of Ledo-carpaceae (x = 9), another segregate of Geraniaceae, and of Balsaminaceae(x = 8 and 7) and Limnanthaceae (x = 5). Vivianiaceae with x = 7 wouldseem to belong with this latter group, the low base number appearing discordantwith the core genera of Geraniaceae itself. TOVARIACEAE Tovaria pendula R. & P. n = 14. Colombia, Antioquia Dcpt., Cainas Gordas,Medellin-Turbo, Gentry & Leon 20205 (COL, MO). Tovariaceae consists of two species in the single genus Tovaria, which rangesfrom northern South America to Mexico. The family is widely accepted as be-776[VOL. 65
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