460 PROCEEDINGS OF THE ACADEMY OF [1897. REPTILES FROM SONORA, SINALOA AND JALISCO, MEXICO, WITH A DESCRIPTION OF A NEW SPECIES OF SCELOPORUS. BY JOHN VAN DENBURGH. This paper is an enumeration of the species of reptiles contained in three small collections, and is presented in the hope that it may be of use to those who are interested in the distribution of Mexican lizards and snakes. Two of these collections are in the California Academy of Sciences: the first, gathered in Sonora by Dr. Gustav Eisen and Mr. Walter E. Bryant in April and May, 1S92; the second, due to the efforts of Dr. Eisen and Mr. Frank H. Vaslit in Sinaloa and Jalisco in October and November, 1894. The third collection was secured by Dr. David Starr Jordan and a j)arty of students at Mazatlan in December, 1894, and January, 1895, and is in the Zoological Museum of Leland Stanford Junior University. 1. Phyllodactylus tuberculosus Wiegm. A fine specimen of this gecko (Cal. Acad. Sci., No. 3,389) was obtained at Matzalan, Sinaloa, in October. The California Academy possesses two specimens (248, 249) secured in Durango by Mr. C. A. Hamilton. 2. Gehyra mutilata (Wiegm.). Eighteen specimens of this lizard (C. A. S.. 3,350-3,367) were collected at San Bias and one (C. A. S., 3,180) at Tepic, Jalisco. Females taken in October contain eggs which must have been nearly ready for laying; femoral pores vary from eleven to twenty on each side. In connection with Dr. Giinther's suggestion that this species has been recently introduced into America, 1 it may be of interest to note that geckos sometimes come to San Francisco in the holds of vessels. 3. Coleonyx variegatus Baird. Several specimens were caught at San Miguel de Horcasitas, in Sonora, in April, 1892. 4. Anolis nebulosus (Wiegm.). Dr. Eisen and Mr. Vaslit secured this species (3,181-3,188) at Tepic, Jalisco, in October. The California Academy possesses also l Biol. Centr. Amer. Rept., 1893, p. 81. 1897.] NATURAL SCIENCES OF PHILADELPHIA. 461 two specimens (C. A. S. 351, 852) caught by Captain Wm, Lund on the Tres Marias. Dr. Jordan's party found the species at Mazatlan. 5. Iguana igvana rhinolopha (Wiegin.). Three specimens were obtained at Mazatlan, Sinaloa, and four (C. A. S., 3,339-3,342) at San Bias, Jalisco. 6. Ctenosaura teres (Harlan). This species is more numerously represented, both in the Stanford University collection and in that belonging to the California Acade- my, than any other species. These specimens were shot at Mazatlan, Tepic and San Bias. Many of these specimens are very large and have dorsal crests so well developed that I have no hesitation in abandoning Cope's brachyloj)ha as a name for them, although I have seen no specimens from near the type locality of Harlan's Cyclura teres. It well may be that western specimens differ from the typical form, but until some better character has been found to separate them I cannot recognize them as distinct. 7. Crotaphytus baileyi Stejn. One specimen was brought back from Hermosillo, Sonora. 8. Callisaurus ventralis 'Hallow). A Gridiron-tailed Lizard (C. A. S., No. 3,390) taken at Mazatlan, Sinaloa, in October, appears to be identical with Californian and Arizonan examples of this species. Its femoral pores, however, are only ten instead of from fourteen to eighteen. This locality is much farther south than any at which this lizard had previously been found. The species was found also at San Miguel de Horcasitas, Sonora, in May, 1892. 9. Holbrookia maculata approximans (Baird). A typical specimen of this subspecies was caught at Duras Nillas, Sonora, in May, 1892. Several young from Mazatlan, January 25, 1895, are also referred to this form, although their snouts appear to be more pointed than those of Arizonan examples. 10. TJta ornata B. & G. This lizard was obtained in Sonora at San Miguel de Horcasitas, in April, and at Duras Nillas, in May, 1892. 11. Sceloporus utiformis Cope. Numerous specimens of this Sceloporus were shot at Tepic, Jalisco, in October. 462 PROCEEDINGS OF THE ACADEMY OF [1897. 12. Sceloporus pyrrhocephalus Cope. A single young male (C. A. S., No. 3,329) agrees closely with Cope's original description of this species. It was found at Tepic, Jalisco, in October. 13. Sceloporus obscurus new species. Two male specimens, one young and one adult, obtained at Tepic appear to differ in important characters from all known species. Type. — Cal. Acad. Sci., No. 3,213, Tepic, Jalisco, Mexico, Gustav Eisen and Frank H. Vaslit, November, 1894. Description. — Upper head-shields nearly smooth ; enlarged supra- oculars in one row, separated from mesial head-shields by a com- plete series of small scales; two scales on canthus rostralis; frontal divided transversely but not longitudinally ; interparietal wider than long ; parietals small ; ear-opening with very slight denticula- tion of scales much smaller than those immediately preceding. Dorsal scales strongly keeled, sharply pointed, without marginal serrations, in nearly parallel longitudinal rows. Laterals keeled and pointed, in oblique rows, changing gradually to the larger dor- sals and smaller ventrals. Twenty-eight to thirty dorsals on a line between interparietal plate and base of tail ; about seven equaling length of shielded part of head. Ventrals smooth, emarginate ; gulars weakly keeled, emarginate. Upper caudals considerably larger than dorsals. Distance between base of fifth and end of fourth toe equals distance between end of snout and posterior bor- der of ear-opening. Tibia equals length of shielded part of head. Sixteen to eighteen femoral pores on each side, the series not meet- ing mesially. Males with enlarged postanal plates. All the upper surfaces are bluish steel-color, lighter and more bluish about the centres of many scales, sometimes with bronze re- flections, without collar or other markings of any kind except indis- tinct cross-bars on the toes. The lower surfaces are similarly colored, but are paler, with a greenish or bronze cast on the throat and chest and a large area of campanula blue on each side of the belly. There is a light streak along the middle of the throat. mm. mm. Snout to anus 70 77 Length of tail — 106 Snout to ear 17 18 Shielded part of head 15 16 Fore limb 35 36 Hind limb 45 59 Base of fifth to end of fourth toe . .18 21 1897.] NATURAL SCIENCES OF PHILADELPHIA. 463 14. Sceloporus boulengeri Stejn. A very large number of Seelopori collected at Mazatlan and Tepic, are certainly identical with Dr. Stejneger's S. boulengeri. I believe that this is the same form as Cope's S. oligoporus. It may even be true that these are not distinguishable from S. horridus, but, without an opportunity to examine the types or specimens from the type localities, it seems best to use a name of unquestionable applicability. 15. Cnemidophorus deppii lineatissimus Cope. Two specimens (C. A. S., 3,344, 3,343) taken at San Bias, Jalisco, in October, 1894, seem typical of this lizard. 16. Cnemidophorus gularis B. & G. A lizard caught at Guaymas, Sonora, May 12, 1892, is identical with Arizonan specimens of this species. 17. Cnemidophorus mariarum Giinther. A large number of lizards from Mazatlan, San Bias and Tepic seem to be identical with Gunther's specimens from the Tres Marias- Islands. Whether they are also identical with Cope's C. communis and Peter's C. mexicanus I have not been able to decide. The upper lateral light lines are much farther apart than in C. gularis, causing the specimens to bear some resemblance to C. sez- lineatus. 18. Sympholis lippiens Cope. One typical specimen (C. A. S., 3,127) of this rare snake was taken at Tepic in October. 19. Bascanion flagellum frenatum Stejn. The cross-bars on the neck are rather faint in a snake of this sub- species (C. A. S., 3,412) which Mr. Bryant procured at Hermosillo, Sonora, in May, 1892. This snake was brought back alive and died in San Francisco in October, 1892. 20. Basoanion semilineatum Cope. This racer was taken by the Academy's collectors at both Tepic (Nos. 3,131, 3,132) and Mazatlan (No. 3,391) in October. 21. Bascanion lineatum Bocourt. A single example (C. A. S., No. 3,130) with one hundred and eighty-four gastrosteges, one hundred and twenty-one urosteges, and scales in seventeen rows, was shot at Tepic in October. 464 PROCEEDINGS OF THE ACADEMY OF [1897. 22. Hypsiglena torquata (Giinth.). The Academy's collectors secured a single representative (C. A. S., No. 3,394) of this species at Mazatlan. 23. Natrix valida (Kenn.). One specimen was secured at Tepic in October. 24. Hapsidophrys diplotropis (Giinth.). Two typical specimens of this beautiful snake were obtained at Mazatlan in October. 25. Sibon punctatum (Peters). Dr. Jordan's party secured a single snake of this species at Mazat- lan. Its scale rows are nineteen and its gastrosteges one hundred and fifty-five. 26. Sibon personatum Cope. One snake of this kind was caught at Tepic, Jalisco, in October. It has one hundred and sixty-three gastrosteges, eighty urosteges, and scales in twenty-one rows. 27. Trimorphodon biscutatus (D. & B.). Two specimens from Mazatlan are in the Stanford University collection. They have gastrosteges 249, 250, urosteges 72, 79, scale rows 24, 25.