2 2 2 Memoir Sears Foundation for Marine Research 



Snout in front of orbits about 3—4 times as long as orbit in small specimens, 4—5 

 times in adults, its length in front of mouth 1.8—2.2 times as great as distance between 

 exposed nostrils in young and old alike. Distance between orbits about as great as 

 length of orbit at hatching, 1.4- 1.7 times when full grown; orbits about 1.8 times as 

 long as spiracles on young but about 1.3 times on adults. Distance between first gill 

 openings 1.8— 2.1 times as long as distance between exposed nostrils, between fifth 

 gill openings 1.2— 1.4 times; first gill openings 1.2— 1.4 times as long as fifth and about 

 18—21 "/o as long as breadth of mouth. Nasal curtain deeply fringed, the individual 

 lobes simple or bifid; expanded posterior (outer) margin of nostrils smooth. Upper 

 jaw nearly straight, lower weakly arched in both sexes. 



Teeth 23^? usually one or two more series in upper jaw than in lower, some- 

 times the reverse; those of females and of immature males close-set in quincunx, their 

 bases nearly circular in outer series but quadrate with rounded corners in central series; 

 the oldest (anterior) four or five rows worn smooth, the youngest (posterior) two or three 

 rows with low conical median cusp; those of mature males more loosely spaced in trans- 

 verse series, with conical cusp, considerably longest and sharpest in the younger rows. 



First and second dorsals similar in size and shape. Interspace between dorsals 

 14—30 "/o as long as base of first dorsal, independent of size or sex. Caudal from 

 rear end of base of second dorsal about 1.5 times as long as base of first dorsal on 

 newly hatched specimens, about as long as base of first dorsal on half-grown spe- 

 cimens, but only about half as long on large. Pelvics noticeably small in area relative to 

 disc, rather deeply concave, strongly scalloped around anterior side of the excavation 

 but only weakly so rearward; anterior margin about V2— ^/d as long as distance from its 

 own origin to rear tip of pelvic; anterior lobe broad, including 5-6 radial cartilages 

 besides the first stout one; posterior lobe strongly convex outwardly; rear tips abruptly 

 rounded, extending rearward about 1/4 the distance from axils of pelvics toward first 

 dorsal. Claspers of sexually mature males conspicuously massive, reaching rearward 

 about 3/4 the distance from axils of pelvics toward first dorsal. 



Anterior rays of pectorals extending about -/g the distance from level of front of 

 orbits toward tip of snout. 



Color. On fresh specimens, the upper surface brownish, with many scattered small 

 darker spots of various sizes, the largest usually about the size of eye, more numerous 

 on some specimens than on others; usually a larger and irregularly elongate spot or 

 blotch on inner part of each pectoral about level with outer corner. Mucous pores on 

 nuchal region and anterior to eyes with black dots (Fig. 47). Lower surface white, 

 frequently blotched irregularly with gray, especially on large individuals; specimens 

 one-third grown and larger always with small black or dusky dots or short streaks 

 marking the orifices of mucous pores, in continuous arcs around midbelts of pectorals, 

 across midzone of disc, and on pelvic regions (Fig. 47 B); also scattered less regularly 

 elsewhere. Very small ones may lack these black markings.** 



46. The mucous pores on the smallest specimens we have seen (about 190 mm long) are only faintly visible after many 

 years in alcohol, but they may have been more conspicuously marked when the specimens were fresh. 



