Benham. —All apparently Neiv Sjjecies of Eegalecus. 199 



middle of the body. These colour-bands are not black, but 

 extremely pale grey, and could only be recognised by reflec- 

 tion in certain lights, the grey being due to minute pigment- 

 cells below the silver. 



The fish is remarkable for its very great length as com- 

 pared with its vertical height, being much more ribbon-like 

 than other ribbon- fishes. Its total length (without the caudal 

 fin) is 45 in. (1,144 mm.) ; it greatest height (at the level of 

 anus) is only 0-75 in. (18'75 mm.) ; its thickness at this point 

 is g^in. (7-3 mm.). This brings the ratio of length to height 

 to about 60. 



The head measures 2^ in. in length (53 mm.), and fin. in 

 height (21mm.). Diameter of eye -Jin. (12mm.); distance 

 from anterior margin to tip of retracted snout is fin. (18 mm.). 



Anus, 13^ in. (337 mm.) from snout. 



Fin-formula: D., 7/390; P., 10; V. (?). 



Height of body, J^ of the total length ; length of head, 

 -i3-\- of the total length ; pre-anal region to total length is 

 i to 3-3. 



The dorsal fin is about half the height of the body, and 

 there are 9 fin-rays to the inch anteriorly — or, roughly, about 

 390 fin-rays altogether. The anterior rays measured along 

 their length are fin. (15 mm.); in the hinder part they are 

 about -Jin. (12mm.) long. The membrane reaches nearly to 

 tips of the rays. The anterior or nuchal portion of the fin 

 was damaged, but the bases of 7 rays remain, which are stouter 

 than the usual rays, and no doubt were elongated, as in 

 B. glesne. The pectoral fin is ^^ in. long, with 10 rays ; the 

 pelvic (broken) are represented by a pair of minute knobs just 

 behind the level of the pectorals on the throat. No doubt 

 they were elongated in life. 



Teeth absent in the upper jaw, but there are two pairs of 

 delicate conical teeth far forward in the lower jaw, and ou 

 the palate a small median tooth. 



The lateral line has a characteristic course : starting from 

 the upper part of the back of the head, it passes rapidly 

 downwards behmd the pectoral fin to gain the lower part of 

 the side, about 1^ in. (28 mm.) behind the head. Thence the 

 right and left lateral lines run backwards parallel, one on 

 each side of the narrow belly close to the ventral mid-line 

 and separated by a distance of |^in. (3 mm.). 



The head has black (not dark-blue, as in B. glesne) pig- 

 ment bordering the lips, and a curved band of the same colour 

 across the forehead, concentric with but slightly removed 

 from the hinder border of the maxillary bone. The top of the 

 head is black. The iris is also partially black, so arranged 

 that the silver portion is a vertical oval, there being a greater 

 width of pigment anteriorly to the pupil than posteriorly. 



