41 



The dorsal fin commences almost exactly midway between the tip of the 

 snout and the tip of the upper lobe of the caudal fin ; the length of its base is 

 equal to that of the snout ; it is roughly triangular and its height is a fifth 

 greater than the diameter of the eye. The anal commences about an eye-diameter 

 in advance of the dorsal and extends to within a very short distance (equal to 

 three-fourths of an eye-diameter) of the base of the caudal. Caudal forked, its 

 length is about one-sixth of the total. Pectorals extending a good deal beyond 

 the origin of the anal. Ventrals very small, in close contact. 



Stomach large, with a csecal sac and a bunch of large pyloric appendages. 

 A large air-bladder with a persistent pneumatic duct much like that of Glupea. 

 Vertebrae 9 + 22. 



Colours silvery grey becoming black along the back. 



14 specimens, from the Andaman Sea, 185 fathoms, 188-220 fathoms, and 

 370-419 fathoms, and from off Madras 145-250 fathoms. The largest specimen, 

 an adult female, is 8 inches long : the largest adult male is 6^ inches long. 



Registered Nos. 13111, 13112, 13114: 13641, 13642: ^, 2 -f, 2 ™ll™ } 



254 to 256 381 



Named after the late Commander R. F. Hoskyn, R.N., who was Superin- 

 tendent of the Marine Survey of India from October 1889 until his death on 

 January 27th, 1892. Most of the success of the " Investigator " during those 

 years was due to his good-natured sympathy, joined to a singular boldness and 

 originality in handling the trawl. 



Family TrlcMuHdCB. 



Thyrsites, Cuv. & Val. 



Thyrsites, Cut. & Val , Hist. Nat. Poiss. VIII. p. 196 : Giinther, Cat. Fishes, II. p. 350. 



" Body rather elongate : cleft of the mouth wide. The first dorsal continu- 

 " ous, with the spines of moderate length and extending on to the second. Two 

 " to six spurious fins behind the dorsal and anal. The greater portion of the 

 " body naked. Several strong teeth in the jaws : teeth on the palatine bones. 

 " No keel on the tail. Seven branchiostegals. Air-bladder present. Pyloric 

 " appendages in moderate number." (Giinther). 



Subgenus Peomethichthys, Gill. 



Promethichthys, Gill, Mem. Ac. Nat. Soi. Vol. VI. 1893, 115, 123: Goode and Bean, Oceanic Ichthyology, p. 

 20O ; Jordan and Erermann, Fishes of North America, Vol. I. p. 882. 



Two finlets behind the dorsal and two behind the anal fin. Ventrals repre- 

 sented by a pair of small spines. No dagger-shaped spine behind the vent. 

 Scales very minute or absent. Lateral line undulating or bifurcating below the 

 front part of the spinous dorsal. 

 6 



