LOPHOBRANCHU. 55 



the In-east -ring, in which there lies a short keel that issues from 

 the occipital one and ends above the gill-opening. There aiv 

 12 rings before tin- dorsal fin, 16 np to the anus, and 14 in the 

 tail. Twenty rays support the dorsal on 7 rings. The upper 

 caudal edge reaches forwards to the under border of the 2nd 

 rinj: of the dorsal fin ; and the caudal fin has !> or 10 rays. 



The colour is brownish-yellow, with a blackish-brown streak 

 along the side of the snout, through the eye and along the back ; 

 the lateral line and the tail are also blackish-brown; while the 

 yellowish caudal is spotted with black. The smaller and younger 

 female specimen is heptangular, with a black belly, and the 

 spines of the back and snout are not so fully developed. 



Genus 2. CH0ER0ICHTHYS, Kp. 



Dingn. — The short body arched on the back and belly. The 

 snout destitute of spines and projections on its under part, 

 slender and rising upwards near the mouth. Lateral line 

 unusually projecting and uniting with the under edge of the 

 tail. On the small nuchal shield there are no pits. The 

 egg-pouches of the males are furnished with a membrane. 

 The fins are not much developed. 



1. Choeroichthys Valenciermi, Kp. 



Descr. — In the Paris Museum there is a male specimen, which 

 was sent from the Isle of Bourbon by M. Mathieu. It is a di- 

 minutive but highly interesting form, which I have named as a 

 testimony of my respect for the great Ichthyologist of the age. 

 The slender snout measured from the nostrils equals the head 

 in length, and is furnished with a crest. A prominent line runs 

 from the hind-head over the eyes to the end of the snout; 

 another descends from the nostrils down to the under border of 

 the orbit, and goes on also to the end of the snout, and there is 

 a third and a fourth on the under borders of the snout. Occiput 

 rough and, like the nuchal shield and dorsal surface of the breast- 

 ring, keeled. A keel divides the operculum into two dissimilar 

 parts. In the upper portion there is an oblique prominent line, 

 and in the under portion there are seven rough cross-lines. 

 From the elongated breast-ring to the dorsal fin there are 1 1 

 rings; 15 rings up to the anus, and 18 in the tail. The dorsal 

 stands on 4 body-rings and 1 caudal ring. The ventral aspect 

 of the breast-ring is keeled, and near the pectoral fin there are 

 two elevated lines. Back concave, with toothed edges. Colour 



