138 Zoological Society : — 



isthmus, scaly. Four gills, a slit behind the fourth ; pseudobranchise 

 none. 



The jaws, vomer, palatines, and upper and lower pharyngeals are 

 armed with bands of small villiform teeth. Very remarkable are two 

 large, ovate, dentigerous plates, one at the roof, the other at the bot- 

 tom of the mouth, in front of the pharyngeals ; these plates are 

 slightly concave in the middle, pavimentated with molar-like teeth, 

 and have evidently the same function as the pharyngeal dentigerous 

 plates of the true Pharyngognathi. 



Total length 52 lines. 



When I composed the generic characters of the genus Catopra from 

 Bleeker's accounts, I had not seen a specimen of these fishes, and I 

 described their peculiar dentition in very indistinct terms. The 

 teeth ought to be described thus : — Villiform teeth in the jaws and 

 on the vomer and palatine bones ; a large patch of molar-like teeth 

 on the prsesphenoid and on the basihyal. 



Catopra tetracanthxjs. 



D. i^^ A. i. L. lat. 26. L. transv. 3/9. 



The height of the bod}- is nearly one-third of the total length. 

 Cheek with four series of scales, the lower prseopercular limb being 

 naked. Coloration uniform ? 



East Indies. 



Description. — The height of the body is nearly one-third of the 

 total length, the length of the head two-sevenths ; head a little longer 

 than high. The length of the snout equals the diameter of the eye, 

 which is contained thrice and two-thirds in the length of the head. 

 The width of the interorbital space is considerably less than that of 

 the orbit. The lower jaw is scarcely longer than the upper, and the 

 maxillary extends slightly beyond the anterior margin of the orbit. 

 Two nostrils remote from each other, the anterior minute. Prse- 

 orbital and angle of the preeoperculum slightly serrated ; opercles, 

 throat, and isthmus entirely scaly. The dorsal fin commences above 

 the root of the pectoral, and terminates at a short distance from the 

 caudal ; its spines are of moderate strength, those in the middle being 

 the longest, a little more than one-third of the length of the head ; 

 the last spine is a little longer thau the penultimate ; the soft dorsal 

 is somewhat elevated and not scaly. The three posterior anal spines 

 are nearly of equal length and strength, two-fifths of the length of 

 the head. Caudal rounded, scaly at the base, one-fourth of the total 

 length. 



Scales minutely ciliated. 



The jaws, vomer, palatines, and upper and lower pharyngeals are 

 armed with bands of small, villiform teeth, the jaws having a pair 

 of small canine-like teeth anteriorly. The roof and the bottom of 

 the cavity of the mouth have an elongate band of granular teeth, 

 the lower not being confluent into one plate. 



The coloration appears to have been uniform. 



Two specimens, 54 lines long, were transferred from the collection 

 of the East India Company to the British Museum. 



