MICHIGAN ACADEMY OF SCIENCE. 91 



at the anterior border of each end of each of the gastrosteges." It seems clear that Cope's 

 assertion of the absence of gastrostegeal spots in hrachystoma is another error since Mr. 

 Brown ('01, p. 29) says of brachystoma: "The color appears to have faded; on stretching 

 the skin indications of the dorsal spots appear and the ventral spots of sirtalis are not ab- 

 sent as stated, in the description (Cope's) but are plainly present though small." The 

 dorsal spots are apparent also in the Olivet specimens of hutlerii, in spite of the fact that 

 their absence is given by Cope as a character peculiar to hrdlerii. Brachystoma and hut- 

 lerii are then clearly identical both in the matter of gastrostegeal and dorsal spots. The 

 same harmony is found in regard to the parietal spots. They are described (Cope) as 

 "faint but present" in the alcoholic brachystoma and "small but present in the usual posi- 

 tion" in butlcrii. 



We thus see that a comparison of the specific characters of brachystoma and hutlerii 

 shows that not only is there no real difference according to Cope's own descriptions but 

 that the characters are identical and that even when there were apparent discrepancies 

 it was due to errors of Cope. When these errors are corrected by observations on a larger 

 number of specimens, brachystoma is found to be identical with hutlerii in these as in the 

 other characters, and since hutlerii is the name first. given, that seems to be the correct 

 name of this sjjecies. 



Brown (Pro. Acad. Xat. Sci. '01, pp. 20-2.S) gives the names 'bracliy- 

 stoina and hutlerii as synonyms of E. sirtalii^ sirtalis. Rnthven appar- 

 ently accepts this dictum with regard to hracliy stoma as already stated, 

 but considers hutlerii a good and valid species. If as contended in this 

 paper hracht/stojita and hutlrrii are the same, then it becomes necessary 

 to clear up the status of hracJiystonta with regard to sirtalis. That 

 hracliystoma is not sirtalis seems to be quite clear when the wide differ- 

 ences between these species are taken into consideration. The surprising 

 thing is not that Brown considers hracliystoiiia and hutlerii to be syn- 

 onyms, but that he should have thought it possible for hutlerii to be the 

 same as sirtalis. The fact that Brown did not distinguish hutlerii from 

 sirtalis is in itself enough to cast doubt upon his statement that hracliy- 

 stoma is in anomalous sirtalis. For the sake of clearness the term 

 hracliystoma will be continued when referring to Cope's type specimen. 



HEAD. 



There is a niarked difference in the shape of the head as a glance at Cope's own figures 

 (Loc. cet.) will show. The head of the sirtalis is larger in proportion to the neck 

 and more distinct from it. A difference more easily seen than described, however. A 

 striking difTerence is found in the length of the mouth. The mouth ends before the poster- 

 ior end of the parietal scuta in brachystoma, l)ut extends considerably beyond in sirtalis. 

 The number of labials for brachystoma is ~f. This number is so small that Brown 

 (loc. cet.) says truly, "it is doubtless correlated with the shortness of the mouth." The 

 fact remains that in this remarkable reduction of labials brachystoma differs widelv from 

 sirtalis. Moreover the difference is very constant. Out of 320 specimens of sirtalis ex- 

 amined by Clark ('03 p. 86) 6 have 6 upper labials on one side but not one has that number 

 on both sides, while twelve have 8 on one side and two have 8-8. Now in a character that 

 is so constant that 94 per cent of sirtalis have 7-7 supra labials, and not one out of 320 

 specimens has 6-6, it would seem that there is a real difference between brachystoma with 

 6-6 and sirtalis with 7-7. In the matter of the lower labials, 8-8 and 10-10, the difference 

 is equally striking. 



Of the 320 sirtalis examined 268 or about 90 per cent have 10 — 10 lower labials, of the 

 remaining 10 per cent only two or .6 of 1 per cent have 8-8, and these are clearly distin- 

 guished from brachystoma by other characters such as number of gastrosteges and virosteges, 

 and shape and length of head and Ijody. 



In view of these facts it seems clear that since .'^~,'^ labials of sirtalis are so constant 



^ ■J 1 u 



both in the upper and lower, the ^rr| labials of brachystoma constitute a specific differ 



6 — 6 



S — 8 



ence. 



