2 04 Memoir Sears Foundatiofi for Marine Research 



but smooth or nearly so in mature males. Alar spines of maturing males in two rows, 

 perhaps more in some cases. Lower surface smooth. 



Snout in front of orbits 2.4-2.9 times as long as distance between orbits, its 

 length in front of mouth about 1.6-1.7 times as great as distance between exposed 

 nostrils. Distance between orbits about as long as horizontal diameter of orbit in young 

 but only about 70-80 "/o as long in adults; orbit about 1.3 times as long as spiracle. 

 Distance between first gill openings 2.0-2.2 times as long as distance between ex- 

 posed nostrils, the distance between fifth gill openings 0.86-1.2 times as long; first 

 gill openings 1.2-1.7 times as long as fifth and about 30-37 "/o as long as breadth 

 of mouth. Nasal curtain and posterior (outer) margin of nostrils deeply fringed. Mouth 

 considerably more arched centrally in adult males than in females or young. 



Teeth 4^50; those of females and of young males closely set, in quincunx, the 

 older rows evenly rounded (as a result of wear), the younger rows with faintly indicated 

 cusp; teeth of adult males spaced more loosely in more nearly transverse series, with 

 blunt-tipped conical cusp. 



Interspace between first and second dorsals about 15 % as long as base of first 

 dorsal, with i-2 thorns." Caudal membrane posterior to base of second dorsal about 

 2/3 as long as base of first dorsal. Pelvics rather deeply concave outwardly, strongly 

 scalloped around the concavity; anterior margin about 48-56 % as long as distance 

 from its own origin to rear tip of pelvic; anterior lobe narrow with rounded tip, including 

 only 1-2 radials besides the first stout one; posterior lobe with weakly convex outer 

 margin and narrow tip. 



Anterior rays of pectorals reaching about ^4 the distance from level of fronts 

 of orbits toward tip of snout. 



Color. Upper surface pale buff or brown freckled with small spots, darker or paler, 

 and conspicuously marked with dark rosettes, each consisting of a group of six or more 

 dark brown or black spots surrounding a central one; rosettes arranged in symmetrical 

 pattern on disc and along tail, with one at origin of each dorsal fin. On specimens only 

 85 mm long, one rosette is already visible on either side of the shoulder region, one 

 opposite and a little behind each eye, and one or two on the tail. Lower surface white 

 or pale yellow. 



Size. This is one of the smaller members of the genus, males maturing at a length 

 of only about 400 mm,!^ no doubt females as well. A specimen of 85 mm is the 

 smallest seen. 



Developmental Stages. Neither the egg cases nor its newly hatched young have 

 been seen. 



Habits. Little is known of its habits. It appears to be restricted to depths greater 



14. The type specimen (Garman, Mem. Harv. Mus. comp. Zool., 36, 1913: pi. 18. fig. 2) has three distinct dorsal 

 fins on the tail. See Schnakenbeck (Zool. Anz., 140, 1942: 88-90) for description and photo of a specimen of the 

 European R. cla'vata with an accessory dorsal fin close behind the pectoral girdle and for references to earlier ac- 

 counts of similar abnormalities. 



15. The claspers of a male 395 mm long in our Study Material already extend more than halfway from the level of 

 the axils of the pelvics toward the tip of the tail; they appear to be fuUy developed or nearly so. 



