MEXICAN SNAKES AND CROCODILIANS — SMITH 417 



DIADOPHIS DUGESII Villada 



One specimen (No. 109935) was taken 6 miles east of Quiroga, 

 Michoacan. It was found under a large stone in an open oak woods, 

 after a heavy shower. 



In addition to this specimen, six others in the National Museum have 

 been examined: Guanajuato (Nos. 11361, 12681) ; Mirador, Veracruz 

 (No. 31051) ; Mexico (Nos. 12728, 26141-2) . The variation in scutella- 

 tion of these follows : Scale rows 17-15 in two, 17-17 in five ; suprala- 

 bials 7-7 in five, 8-8 in two ; inf ralabials 7-8 in one, 8-8 in five, 8-10 in 

 one ; three postoculars on one side in two, otherwise two preoculars and 

 two postoculars ; temporals 1-2 on one side in two, on both sides in four, 

 1-1 on one side in two, on both sides in one. Ventrals and caudals in 

 the order listed above : 178, 56 ( $ ) ; 207, 53 (?) ; 201, 52 ( 5 ) ; 180, 57 

 ( $ ) ; 177, ? ( S ) ; 179, 57 ( 2 ) ; 205, 53 ( 5 ). The range in ventrals 

 and caudals of five males now known of the species is 177 to 183, 56 to 

 57, respectively, in five females, 201 to 207, and 49 to 53, respectively. 

 In no specimen does the white of the ventral surface extend onto the 

 first row of dorsal scales. 



The maxilla of the Michoacan specimen has nine subequal teeth, 

 followed after a long diastema by two much enlarged, ungrooved 

 (although flanged) teeth, which are distinctly offset from the other 

 teeth. 



This species is very distinct from regalis, differing by having the 

 white of the ventral surface not encroaching upon the first row of 

 dorsal scales (does in regalis), a distinctly lower ventral count (more 

 than 206 in males, more than 220 in females of regalis), usually 17 

 scale rows posteriorly (rarely 17 in regalis). These differences may 

 be subspecific, but they are so great that they are here considered 

 specific. D. regalis has a maxillary dentition exactly like that of the 

 specimen described of dugesii. 



The proper orthography of the specific name of this species is 

 dugesii, not dougesii as it was spelled in the original description. Two 

 reasons support this conclusion: (1) The species is named for Duges; 

 (2) the spelling is corrected in two places in the same volume. In 

 the index to that volume, the article is listed "El Diadophis punctatus, 

 v. Dugesii." In the page of "Erratas Notables del Tomo III," the 

 correction is made in the spelling of the name in the description itself 

 ("Pagina 226, Dice DOUGESII, Debe Decir DUGESII"). 



♦DRYADOPHIS MELANOLOMUS MELANOLOMUS (Cope) 



The Museum has three specimens, including the type (No. 24985) ^ 

 and two others (Nos. 10302, 24986) from Yucatan. 



» Cope, 1868a, p. 134. 



