454 



BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



of the head. The maxillary extends slightly beyond the hind margin 

 of the pupil. The outer premaxillary series of teeth are scarcely en- 

 larged. There are six branchiostegals ; a narrow free fold is formed 

 behind the attachment of the gill-membranes. 



The location of the anus is subject to variation, its distance from 

 the origin of the anal being contained 3.0 (2.0 to 3.7) times in the dis- 

 tance from the anus to base of outer ventral ray, a distance about 

 equal to that from the ventral to the isthmus, and contained 1.15 

 times (1.0 to 1.2) in the postorbital length of the head. 



The ventral fossa in this species is a scaleless strip extending for- 

 ward from the peritroct. Its shape is variable; in some specimens it 

 is narrow and rectangular, of variable width, but is usually widest 

 anteriorly, as in the type ; in one specimen it has an obovate form ; its 

 surface is punctate. Above the fossa a peculiar organ is imbedded, 

 resembling that of ('. maculatus, but apparently differing from it in 

 certain details: it is an elongate, flat body, darkly pigmented on its 

 ventral surface, but wholly silvery on its dorsal surface ; a strand of 

 tissue, about as long as the organ, connects it with the peritroct. 

 The organ has no skeletal support. 



Table of scale and ridge characters. 



i Type. 



The spinous carinae of the scales do not approach, either in size 

 or strength, those of C . maculatw, but are stronger than those of C. 

 notatus. The rather weak spinules on the scales of the body are 

 imbricate upon one another; the last spinule in each series projects 

 but little beyond the margin of the scale; the 11 or fewer spinules 

 on each of the carinae increase but little in strength posteriorly on 



