I 3 2 



2. Sternoptyx Hermann. 

 (HERMANN, Der Naturforscher, XVI. 1781, p. 8). 



Trunk much elevated and compressed, passing ventrally 

 abruptly with a more or less right angle into the short and 

 compressed tail; the angle being filled up by a transparent fold 

 of the integument, resembling thin cartilage. A similar structure 

 forms the ventral edge of the trunk. Cleft of mouth subvertical, 

 its upper margin formed by the very short intermaxillaries and 

 maxillaries. Lower jaw received in the upper, its posterior 

 inferior angle has a short spine as also the angle of the prae- 

 operculum and the symphysis of the humeral bones. At the 

 symphysis of the pelvic bones two spines, one looking forward, 

 the smaller backward. Behind the anus a bifid spine. Before 

 the dorsal, the origin of which is situated behind the middle 

 of the body, a translucent pear-shaped plate, which has its upper 

 border dentated, strengthened along its hindmargin by a strong 

 spine. Anal arising on the broad transparent integumentary 

 fold between trunk and tail. The low adipose fin begins imme- 

 diately behind dorsal and reaches nearly to the anterior rays 

 of the caudal, which is broad and forked. Pectorals close to 

 the ventral profile, surpassing the base of the ventrals. Ventrals 

 small. Eye large, snout very short. Numerous small unequal 

 teeth in the jaws. Palate edentulous. No scales. Luminous 

 organs: one behind and one below the eye, one opercular, a 

 group on branchiostegal membrane, a group on isthmus, a series 

 along ventral edge, one series between ventrals and anal, above 

 anal, behind anal and above pectorals. Gillopening very wide, 

 gillmembranes attached to the isthmus. 4 gills. Pseudobranchiae 

 present. Gillrakers moderate. 



i. Sternoptyx diaphana Herm. 



Sternoptyx diaphana Hermann, Der Naturforscher, XVI. 1781, p. 8. 

 Sternoptyx diaphana Gunther, Challenger Report Deep-sea Fishes, 1887, p. 168. 

 Sternoptyx diaphana Brauer, Deutsche Tiefsee-Exp. Tiefseefische, 1906, p. 115. 

 Sternoptyx diaphana Zugmayer, Camp. Scient. Monaco, XXXV. 191 1, p. 54. 

 Sternoptyx diaphana Max Weber, Siboga-Exp. Fische, 1913, p. 22. 



B. 5; D. 912; A. 1314; P. 10; V. 5. 



Height generally equal to distance between snout and base 

 of tail but varying very much according to length. Length 

 of head 2 ! / 2 to more than 3, generally more or less below 3. 



