GyMNOTID.E. 127 



Ditif/n. The most abbreviated species, with a suddenly-shortened 

 tail, ^Yhose anal fin reaches closely up to the caudal fin. Gape of 

 the mouth extending distinctly beyond the eyes. Anus situated in 

 the front of the cutaneous part of the expansive, boat-shaped 

 mandible. Dorsal thong black above, flesh-coloured on the under 

 surface, with black points on its sides,* and reaching to within an 

 inch of the caudal fin. Pectoral equal in length to the orifice of 

 the mouth. Anal lin commencing before the gill-opening, and ex- 

 tending backwards to the caudal fin. Lateral line protected by 

 keeled scales, with notched points. The other scales are pretty 

 smooth and moderately large. 



Head bluish-black, with lighter, almost white, upper lip and 

 mandible. Back dark brown, dotted with dark spots near the anal 

 fin. P. 16; A. 165; C. 14 Rays. 



The Paris Museum possesses a specimen obtained from Count 

 Castelueau. 



4. Sterxarchus oxyrhinchus, fig. 2. 



Srernarchus oxyrhinchus, Johan. Midi, d Trosch. Flora Ichtli. iii. 

 16, t. 11, f 1, 2 (excellent). 



Ficr. 9. 



Diar/n. The snout forms a long, slender tube, arched below, with 

 a small mouth at its extremity. 



Descr. This is the longest and most compressed species. In the 

 upper jaw there are two clusters of teeth, which are prolonged each 

 into two rows. The eyes are situated between the second and last 

 third parts of the length of the head. Their distance from one 

 another equals two diameters of the orbit. Behind the anal fin the 

 tail is sharply keeled. Lateral line keeled by the arrangement of 

 large scales that accompany it. On the back and over the anal fin 

 the scales are small. Anus situated beneath the eyes. Between 



* Cuvier was the first to make the erroneous assertion that this dorsal thong is a 

 detached cutaneous muscle of the tail. More lately Professor Keinhardt supports 

 this opinion in Wiegmaa's .Journal for 1854, p. 183, and remarks that the thong is 

 never observed to be free in the living fish, and that it becomes loose in alcohol, 

 through handling. Since no muscle can become dotted with black on its fleshy 

 side, we may conclude that the thong, though held fast in its furrow by the slimy 

 mucus of the body, becomes free by means of the action of the alcohol on that 

 mucus. 



