167 



Dorsal fin short, in the middle or anterior half of the body : anal fin long, 

 in the posterior half of the body. Caudal forked. Adipose fin small, placed far 

 back. 



Pectorals and ventrals well developed, the pectorals inserted near the 

 ventral profile, the ventrals inserted below the dorsal some way behind the 

 pectorals. 



Distribution : Mediterranean, Bay of Bengal, Andaman Sea. 



135. Odontostomus atrattis, Alcock. 



Odontostomus atratus, Alcock, Journ. As. Soc. Bengal, Vol. LXII. pt. 2, 1893, p. 182, pi. ix. fig. 4 : Illustrations 

 of the Zoology of the Investigator, Fishes, pl. XXXIII. fig. 3. 



B. 8. D. 11. A. 26. P. 12. V. 8. 



The extreme length of the square, high, compressed head is a little more, 

 and the greatest height of the compressed tapering body is a little less, than one- 

 fourth of the total, caudal included. 



The snout has the form of a pointed wart beyond which the upper jaw 

 slightly projects, the lower jaw again projecting a little beyond the upper. 



The eyes, which are situated about a diameter apart, near the top of the 

 head, have their major diameter obliquely vertical, and are capable of such 

 strong rotation inwards as to bring the visual axis obliquely upwards, the orbit 

 being walled in laterally by a stout but transparent fold of skin in its lower half. 



The cleft of the mouth extends almost to the posterior edge of the preoper- 

 culum : the premaxillge are armed with a series of close uniform serrations for 

 the most part pointing forwards, the vomer bears on each side a sabre-shaped 

 depressible fang nearly half as long as the head, the palatines have each an 

 exactly similar fang succeeded by a row of close serrations, and the mandible 

 has on each side a distant series of similar fangs of unequal size, the largest of 

 them however being hardly half the length of those on the vomer and palatines. 



Gill-cleft extremely wide and high : four gills with wide lamina3 and gill- 

 rakers inconspicuous or absent : pseudobranckias large. 



Body covered with a glandular scaleless skin in which the lateral line 

 appears in spirit as a white streak. Rows of white dots (luminous organs ?) 

 exist along the free border of the preoperculum and the inner border of the 

 broad boat-shaped mandible. 



The dorsal fin lies altogether within the anterior half of the body : the anal 

 begins about half a head length behind the vertical through the last dorsal ray, 

 and extends to the rudimentary basal rays of the forked caudal. The large 

 pectorals arise close to the ventral profile, almost in the same plane with the 



