398 Memoir Sears Foundatioft for Marine Research 



base a little posterior to rear end of base of anal, its tip a little posterior to tip of anal, 

 its apex only very narrowly rounded, its free rear corner slender and about as long as 

 base. Caudal about Yi of total length, its upper margin slightly to moderately convex, 

 its terminal sector tapering and a little less than ^,4 the length of fin, with narrowly 

 rounded tip and weakly concave lower posterior margin, the lower lobe a Jittle less than Y2 

 as long as upper with its tip narrowly rounded, the re-entrant corner (enclosed by the 2 

 lobes) more obtuse than a right angle and broadly rounded. Distance from caudal to tip 

 of anal about as long as base of anal in smallest specimens but only about 73 that long in 

 larger. Anal about i.o to 1.3 times as long at base as 2nd dorsal, its anterior margin much 

 more strongly convex and posterior margin much more deeply concave, its apex more 

 rounded, its free corner slender and about as long as base or slightly shorter. Distance from 

 origin of anal to tips of pelvics a little longer than base of anal. Pelvics with nearly straight 

 anterior and posterior margins, about as long at base as anal. Pectoral noticeably small, 

 about % as long as head or only a little longer than anterior margin of ist dorsal and a 

 little more than Y^ as broad as long, the outer margin only very weakly convex, the distal 

 margin weakly and evenly concave, the tip and inner corner very narrowly rounded. 



Color. Described as leaden or bluish gray above, the sides sometimes tinged with red- 

 dish, the lower surface pale 5 the pelvics sometimes with reddish tinge toward their bases j 

 edges of lower fins and hind edge of lower caudal lobe white. 



Size. The largest specimen so far recorded was 1,235 mm. (49 inches) long."^ The 

 fact that the claspers in an 831-mm. Pacific specimen are twice as long as the pelvic fins 

 suggests that this shark does not reach a length much greater than perhaps four feet. 



Develo-pmental Stages. Embryos have not been described as yet. 



Remarks. The specimens listed above can be referred to forosus without hesitation, 

 so clearly diagnostic are the original account and illustrations of that species."^ 



Habits. The localities of capture, listed below, show this to be a strictly subtropical- 

 tropical species and probably littoral. But nothing more is known of its habits. 



Relation to Man. Saleable for human food in the markets of Colon and Panama. 



Range. Western tropical Atlantic; northern Brazil to north shore of Gulf of Mexico; 

 also eastern tropical Pacific, Peru to Panama;"' represented on the Atlantic coast of North 

 Africa by a form that may finally prove to be identical."* 



141. Herre, Field Mus. Publ. Zool., 21, 1936: 22; a Pacific specimen. 



142. Ranzani, Nov. Comment. Acad. Sci. Inst. Bonon (Bologna), ./, 1839; 8, pi. 2. 



143. Our comparison of specimens from Payta, Peru and Panama with others from the Atlantic corroborates Meek 

 and Hildebrand's (Field Mus. Publ. Zool., 75 [i], 1923: 49) conclusion that examples from the two sides 

 of the Isthmus of Panama represent only a single species, which they recorded and described as cerdale Gilbert, 

 1898. But we find nothing to separate the latter from the original account and illustrations of forosus Ran- 

 zani, 1839. And we should perhaps point out that Carman's (Mem. Harv. Mus. comp. Zool., 36, 1913: 131) 

 account of forosus as with broadly rounded snout and with nostril as far from end of snout as from eye, charac- 

 ters used by Meek and Hildebrand in their Key as alternative between forosus and cerdale, does not fit the West 

 Indian and Brazilian specimens in the Museum of Comparative Zoology, from which Carman's description 

 appears to have been taken. 



144. Carckarias fissidens Bennett (Proc. zool. Soc. Lond., 1830-1831: 148), in which the origin of the second 

 dorsal is described as over the middle of the anal and the outer edges of the teeth as deeply notched. But the 

 account of it is not detailed enough for decision. 



