250 BULLETII^ 15 4, UNITED STATES XATIOIs^AL MUSEUM 



bricatis; supra virescens, ad latera fasciis transversis nigrofuscis 

 vittisqiie diiabus pallidis variegatis." An English translation of this 

 diagnosis may be given thus : "" Gular scales subequal, small, elongate; 

 mesoptychial scales moderate, imbricate; greenish above; variegated 

 at the sides with transverse blackish bands and with two pale stripes.'' 



The original diagnosis Avas elaborated with the following descrip- 

 tive paragraph : " Latera dilute fusco-olivacea vittaque longitudinali 

 pallida utrinque marginata, fasciis permultis transversis e fusco 

 iiigricantibus variantur. Vittarnm lateralium altera pone occiput 

 juxta dorsum excurrens in caudae origine desinit, altera illique paral- 

 lela prope scuta suborbitalia incipiens et in inio latere continuata 

 ante femora evanescit." In English, this reads as follows : " The 

 sides, pale olive blackish, and bordered laterally with a pale longi- 

 tudinal stripe, are varied by ver}^ many transverse bands, dusky to 

 blackish. Of the lateral stripes, one, extending back of the occiput 

 close to the back, ends at the base of the tail, and the other, parallel 

 to it, beginning near the suborbital scales and continuing on the side 

 disappears in front of the femur.'' 



Erom the diagnosis and description it is seen that sackil belongs 

 either to the sexUneatus group or to the tesselJahis group, both of 

 which have representatives in Mexico. Moreover, it is evident that 

 the prominent barring on the sides excludes the possibility of identity 

 with any of the Mexican species but gularis^ 'perplexus, and tesseUatus. 

 Further discrimination is difficult. 



It will be noted that nothing is said concerning the ventral colora- 

 tion. A blue-black color would exclude the possibility of identity 

 with perijlexus or tesseUatus, and a coal black color (if not due to 

 fading) would signify the latter form. Likewise, the character of 

 the postantebrachial scutellation is not mentioned. The presence of 

 enlarged scutes would signify gularls or perplexus, but their absence 

 would not be diagnostic. Also, measurements are not given. If the 

 type is small and the sides are reticulated, it is fairly certain tliat it 

 is tesseUatus, but if it is large, this i« no criterion. 



Witii this indefinite background it is not suprising that later 

 writers have not been agreed as to the identity of sackil. In 1856, 

 Lichtenstein reported it not only from Mexico, but from Montevideo 

 in Uruguay as well. The latter report is certainly not based on a 

 specimen of CnemidopJwrus. Bocourt (1874) assigned specimens 

 from Oaxaca to sackil and since perplexus and tesseUatus are absent 

 from the region, it is fairly certain that these were gularis. The same 

 may be said of the records presented by Sumichrast (1884, p. 39) 

 who obtained examples from the states of Oaxaca and Vera Cruz. 



However, Peters, Boulenger and Giinther all regarded sacMi as 

 a synonym of tesseUatus, and Gadow (1906, p. 375) wrote that 

 "Peters has remarked that C. tlgris (= tesseUatus) B. & G. is 



