168 PROCEEDINGS OF THE ACADEMY OF 



maxilliped, and in the presence of a tooth on the inner margin of the mero?, as 

 well as by the entire and plain margin of the median caudal lamina. Other 

 differences seem to exist, which a comparison of the species would probably 

 substantiate. The two species are also inhabitants of very distinct zoological 

 regions, the Callianidea typa being a native of the shores of New Ireland, 

 while the C. laevicauda was obtained under rocks, within coral reefs, at the 

 Island of Barbados, in the West Indies. The size of the two species is nearly 

 similar. 



Description of a new genus of SALARIAN.BE, from the West Indies. 



BY THEO. GILL. 



Entomacrodus Gill. 



Body naked, elongated and slender, slowly declining to the caudal. Head 

 obliquely compressed, oblong subquadrate, and with the profile vertical. Oper- 

 cula unarmed. Eyes lateral, closely approximated, situated at the angle of the 

 profile with the postocular region. No superciliary or nasal tentacles or append- 

 ages. Branchial apertures continuous under the throat. Branchial membrane 

 free and dilatable. Branchiostegal rays six. Mouth moderate, with the con- 

 tour of the upper jaw semicircular ; upper jaw protruding beyond the lower. 

 Lips moderate, uniform and free, concealing the teeth. Teeth labial and move- 

 able, very slender and recurved, contiguous and uniserial. Lower jaw with an 

 interior very large and recurved tooth on each side, which is received into a 

 corresponding fossette of the palate. Dorsal fins disconnected, nearly equal to 

 each other in length ; the posterior free from the caudal. Anal equalling or 

 exceeding the second dorsal. Caudal with its posterior mai'gin obtusely 

 rounded. Pectorals moderate, angularly rounded. Ventrals approximated, 

 each with three simple rays, the internal of which is smallest. 



On a comparison with a true species of Salarias, this genus is found to differ 

 in its more elongated form, by the separate dorsals, and by the absence of any 

 superciliary appendages. The canine teeth of the lower jaw are greatly devel- 

 oped, but they are found of nearly equal size in several species that have been 

 referred to the genus Salaricts. One of the species so distinguished is an inhab- 

 itant of the West Indian seas, and has been described under the name of Sala- 

 ricts atlanticus, by Ouvier and Valenciennes, in the Histoire Naturelle des Pois- 

 sons. That species has an oblong body, superciliary appendages, and the dor- 

 sals connected at the base, and is therefore a true Salarias. 



E. Nigricans Gill. The elongated body, from the snout to the end of the 

 caudal fin, is between seven and eight times longer than it is high at the pec- 

 torals ; its height at the caudal is about a thirteenth of the same length. 



The head is subquadrate, and forms two-ninths of the total length. Its 

 greatest height equals two-thirds of its length. It sides decline obliquely out- 

 wards and downwards. 



The first dorsal commences near the nape, and two of its rays are in advance 

 of the pectorals. The second dorsal commences immediately behind the first, 

 and nearly over the fourth ray of the anal; it ceases some distance from the 

 base of the caudal. The anal is more uniform in height than the dorsal, and 

 ceases before it does. The caudal forms less than a fifth of the total length. 



D 11, 15; A 17 ; P 15; V 3. 



The general color of the body and fins is blackish. 



A single specimen was caught in shallow water, at the island of Barbados, 

 near Bridgetown. 



[June, 



