66 PROCEEDINGS OF THE ACADEMY OP 



and sixth elongate. Inferior labials ten, mostly transverse ; four 

 pairs of geneials, all except the first broader than long. Tail short, 

 m. .047 in length, from a total of ni. .243. 



Color pale, with black transverse spots, which are wide ante- 

 riorly (the second covers seven transverse rows of scales) and 

 become gradually narrower, having a width of only two cross-rows 

 on the hinder part of the body. Posteriorly their lateral ends 

 are broken off, and alternate Avith the dorsal portion. A few small 

 blotclies on the ends of the gastrosteges. 



This serpent and two fishes were presented to the Academ}' of 

 Natural Sciences with the statement that they wei'e derived from 

 some portion of the Peruvian Andes, from an elevation of twelve 

 thousand feet. One of the fishes is Trichomycterus dispar, C. Y., 

 and the other is described below as Protistius semotilus} 



' Protistius semotilus, gen. et sp. nov. 

 Family ?MugilidfB. 



First dorsal fin represented by a single rudimental spiue ; second ori- 

 ginating a little behind the line of the first anal radii. Ventrals present ; 

 lateral line rudimental. Mouth bordered above by the premaxillary only, 

 whicli supports a band of rather large bristle -like teeth, those of the outer 

 series the largest. Dentary bones with strong symphj'sis, with a band of 

 teeth like those of the premaxillary. Swim-bladder present ; alimentary 

 canal short, simple. 



Char. Sjjecif. Snout conical both from the lateral and vertical views. 

 Premaxillary bone viewed from above, wide and angular crescentlc ; top 

 of head moderately convex in cross section, its integument not separated 

 by a fold from the premaxillary. Lower jaw horizontal and angulated at 

 the rictus, and symphysis, as in the genus Mugil. Pectoral fin elevated, 

 rather short, the ventral commencing below its apex. Fin radii D. I. 1. 10 ; 

 P. 15; V. 5; A. I. 13; C. forked 2-J-8 94-2. Scales 48117; lateral 

 line very imperfect ; isolated tubes visible at various points between scapula 

 and tail. Head a little more than four times in length minus caudal fin ; 

 depth of body 5.5 times in the same ; caudal peduncle deep. Eye with 

 round adipose margins, 4.75 times in length of head, and twice in inter- 

 orbital width. Top of head, opercula, and cheeks entirely scaled, the latter 

 in four rows. 



Above olivaceous, below yellow, a broad lead-colored lateral band on the 

 posterior .66 of the length. 



Length to opercular border m. .027, to ventral fins .052, to first dorsal 

 .066, to second dorsal .078 to end of caudal fin .140, all axially measured. 



There are three gills and a half, and no pseudobranchus ; the first bran- 

 chial arch is the only one furnished with rakers. Branchiostegal radii six. 



In its physiognomy this fish is intermediate between that of the MugilidcB 



