﻿New Genera and New Species of Fishes 



MICROGENYS g n. n v. 



Type, 2IiciO(7C)ii/s minufii.s sp. nov. 



Allied to Creagmtiis and Biyeonamerieiis. liaving the anal like the 

 former and the teeth like the latter. 



Microgenys minutus yp. uov. 



Type, 45 mm. CM. No. 5007; two paratypes, CM. No. 5008; I.U.M. 

 No. 12818. Piedra Moler. 



Head 4-4.88; depth 4: I). 10: A. 10; scales 4-35 (about) -2.5; eye .7 

 in snout, 8 in head. 1 in interorbital ; depth of caudal peduncle a little 

 more than 2 in the length of the head. 2.4 in its own length. 



General aiipearance of Crccninitus Ijrcriijiiinis E. from the same local- 

 ity, but a little more slender. Predorsal area rounded, with about 11 

 median scales: ventral surface broad, rounded; occipital process very 

 short, about one-seventh of the distance from its base to the dorsal; skull 

 smooth, rounded: frontal fontanel about half as long as the parietal; 

 snout very blunt, rounded, the jaws equal, the lower slightly projecting 

 when the month is open ; second suborbital about three-fourths as wide 

 as eye, in contact with the lower limb of the preopercle ; mouth very 

 small, maxillary-premaxillary border only about three-fourths as long as 

 eye ; four teeth in the outer row of the premaxillary. the lirst and third 

 slightly withdrawn from the rest, four teeth in the inner series, the two 

 median ones of the two premaxillary unusually close together ; three small 

 teeth on the maxillary; tive to seven graduate teeth on the mandible. 

 Teeth brown-tipped, each with a large triangailar median cusp and a very 

 minute lateral cusp near the base on each side. 



Gill-rakers 5 + 9. 



Origin of dorsal almost exactly equidistant from tip of snout and 

 base of middle caudal rays : margin of dorsal truncate, rays nearly coter- 

 minous ; distance between dorsal and adipose 4J in the length ; caudal 

 forked, the lobes more than 4 in the length ; anal short, slightly emarginate, 

 its highest rays not reaching tip of the last, its origin under end of the 

 dorsal ; ventrals short, about two-thirds the length of the head, their 

 origin in advance of the vertical from the origin of the dorsal, not reach- 

 ing anal ; pectorals shorter than the head, not reaching the ventrals ; scales 

 thin, deep : caudal naked, about three scales of the sides forming a basal 

 sheath for the anterior part of tlie anal. 



A median, silvery band. 



ZYGOGASTER gen. nov. 



Typ,e. Zj/goaaster filifcrus sp. nov. 



Premaxillary teeth in two series, five teeth in the second series, caudal 

 and anal naked ; lateral line complete : maxillary with teeth along its 

 upper angle only. Origin of dorsal a little in advance of the middle ; sec- 



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