Fishes of the Western North Atlantic 477 



% as long at base as ist and about % to % as high vertically, its posterior margin much 

 more deeply concave, free rear corner about as long as base, the spine extending nearly or 

 quite to apex in female as well as in male. Interspace between 2nd dorsal and caudal about 

 twice as long as base of 2nd dorsal. Caudal about Vs of total length (as in acanMas), its tip 

 perhaps averaging a little narrower than in acanthias, its lower lobe a little less than % 

 (about 60%) as long as upper, the general posterior contour, as included by the 2 lobes, 

 much as in acanthias (cf. Fig. 87 with 89). Pelvics about as long at base as 2nd dorsal, the 

 posterior margins more nearly straight and posterior corners perhaps averaging a little less 

 slenderly pointed than in acanthias, the midpoint of base in female nearer to origin of 2nd 

 dorsal than to rear end of base of ist dorsal by a distance only about V2 as long as horizontal 

 diameter of eye and about midway in male (much nearer 2nd dorsal than ist in both sexes 

 of acanthias). Claspers of adult male not subdivided at tip (subdivided in acanthias, p. 

 459). Pectoral a little more than % (69 to 70%) as long as head (about % in acanthias 

 or even a little more), its outer margin rather strongly convex toward apex, distal mar- 

 gin deeply and evenly concave (more deeply so than in acanthias) , the apex rounded, but 

 inner corner considerably produced and acutely angular, this being the most distinctive 

 feature of the species. 



Color. Dark gray above, paler gray below, the young paler than adult; described, 

 when fresh-caught, as having upper lobes of both dorsals black, the caudal, pelvics and 

 pectorals edged with white and the iris green; after preservation the fin markings are much 

 stronger in the young than in the adults. 



Size. The only available information is that the male listed above has large claspers, 

 suggesting that maturity is reached at a length not much greater than 500 mm., i.e., some- 

 what smaller than in the case of acanthias, although it may be as large as the latter at birth. 



Developmental Stages. Probably the early stages in development (not yet described) 

 correspond to those in acanthias. Embryos with a yolk sac already show the bilobed nostril, 

 the shape of the pectoral, the relative positions of dorsal and pelvic fins and the long fin 

 spines characteristic of the adult. 



Remarks. This Shark was first described and unmistakably pictured as long ago as 

 1787 by Parra; although this Dogfish is very different from the northern S. acanthias, it 

 was overlooked until 1936, when it was named by Howell-Rivero (see Synonyms, p. 478). 



Habits. The fact that all specimens so far taken (about 20 in number) have been from 

 depths greater than 75 fathoms suggests that it is a deep-water species. Nothing further 

 is known of its habits, its breeding season or its diet. 



Range. S. cubensis has been reported under this name only from the vicinity of 

 Havana and Matanzas, Cuba. But no doubt most of the Cuban reports of acanthias 

 actually refer to it,°° for specimens of all sizes, including pregnant females, are caught 

 commonly at mid-depths off the north coast of Cuba.'^ While none have yet been reported 

 from the south coast, this is probably due merely to the failure of local fishermen to 



60. See p. 4.63 on this point. 6i. Personal communication by Luis Howell-Rivero. 



