6. SCOPELUS. 405 



The species may be referred to the following subgenera : — 



A. The anal fin has more rays than, or as many as, the dorsal. 



a. Eye large, one-third or more than one-third of the length of the 



head ; no spine above the orbit. 

 a. Scales smooth : Myctophum, m., p. 405. 

 /3. Scales denticulated : Dasyscopelus, m., p. 411. 



b. Eye large ; a horizontal spine above the orbit : Ceratoscopelus, m., 



p. 412. 



c. Eye of moderate size, less than one-third of the length of the head. 



a. Scales smooth, those of the lateral line much larger than the 



others : Alysia, Lowe, p. 413. 

 /3. Scales smooth, subequal in size : Larnpanyctm, Cocco, p. 414. 

 y. Scales covered with minute spines : Neoscopelus, Johnson, p. 414. 



B. The dorsal fiu has more rays than the anal. 



a. Scales of the lateral line considerably larger than the others, p. 415. 



b. Scales of the lateral line not much larger than the others : Not<s- 



scopefus, m., p. 415. 



A. The anal fin has more rays than, or as many as, the dorsal. 



a. Eye large, one-third or more than one-third of the length of the head; 

 no spine above the orbit. 



a. Scales smooth. 



1. Scopelus rissoi. 



Scopelus rissoi, Cocco, in Giorn. Sicil. fasc. 77. p. 144, and Lett. s. 

 Salmon, p. 15. tab. 2. fig. 5 ; Bonap. Faun. Ital. Pesc. c. fig. ; Cuv. 

 fy Val xxii. p. 446. 



D. 13-14. A. 17-18. V. 8. L. lat. 32. L. transv. 2/4. 



The height of the body is contained thrice in the tota\length (with- 

 out caudal), the length of the head twice and two-thirds ; the least 

 depth of the tail is one-third of the height of the body ; the depth 

 of the head equals the distance between the anterior margin of the 

 orbit and the end of the gill-opening. Eye very large, its diameter 

 being contained twice and two-thirds in the length of the head ; 

 the distance between the posterior margin of the orbit and the praa- 

 opercular edge is one-fourth of the diameter of the eye. Snout very 

 short and obtuse, its upper and lower profiles being nearly equally 

 curved. Cleft of the mouth oblique, with the lower jaw scarcely 

 prominent beyond the upper ; the maxillary reaches to the angle of 

 the praeoperculum and terminates in a triangular dilatation. The 

 origin of the dorsal fin is a little nearer to the root of the caudal than 

 to the extremity of the snout, and behind the base of the ventral ; its 

 last ray is in the vertical from the fourth or fifth anal ray. The 

 pectoral fin extends to the anal. Scales smooth, those of the lateral 

 line being nmch elevated, but short : there are six scales between the 

 adipose and caudal fins. No pearl-coloured spot on the back of the tail. 



Mediterranean ; Madeira. 



a-b. From one to two inches long. Mediterranean. 



