Fishes of the Western North Atlantic 407 



tance from origin of caudal to tip of anal about % as long as base of latter. Anal a little 

 longer at base than 2nd dorsal and a very little higher vertically, its posterior margin much 

 more deeply concave, its free rear corner about % as long as base. Distance from origin of 

 anal to tips of pelvics only about % as long as base of anal. Pelvics about as long at base as 

 base of anal, or a little longer, their outer corners approximately a right angle (less obtuse 

 than in obscurus). Pectoral about % as long as head, a little less than V2 as broad as long, 

 with narrowly rounded tip and inner corner, weakly and evenly convex outer margin, and 

 distal margin deeply concave proximally. 



Color. After preservation the type specimen is olive gray above, and of a paler shade 

 of yellowish olive below, without any conspicuous fin markings, dark or light. 



Size. The fact that the type specimen still shows the umbilical scar, although it is 805 

 mm. long, suggests that this is one of the larger members of its genus. 



Develof mental Stages. Embryos have not been seen as yet. 



Habits. Nothing is known of the life history of this newly described species. 



Range. C. springeri is known only from Cozumel, east coast of Yucatan, and (prob- 

 ably) off the west coast of Florida j see Study Material, p. 404. 



Synonyms and References: 



Eulamia sfringeri Bigelow and Schroeder, Proc. New Engl. zool. CI., 23, 1944: 30, pi. 9, lO (descr., ill., 

 Cozumel). 



Family SPHYRNIDAE 

 Hammerhead Sharks 



Characters. In general the characters are those of the Carcharhinidae (p. 262), except 

 that the anterior portion of the head is much flattened dorso-ventrally and very widely ex- 

 panded laterally in "hammer" or "bonnet" form, with the eyes at its outer edges j and the 

 skull is modified accordingly, its anterior portion with the olfactory capsules and orbital 

 region being very widely expanded, and the three rostral bars transversely and broadly 

 truncate in front at their union. Development viviparous, with yolk-sac placenta in some 

 species,' but perhaps ovoviviparous in others. 



Genera. Two, as indicated in the following Key. 



Key to Genera 



I a. Nostrils closer to midline of snout than to eyes. Eusphyra Gill, 1862. 



Tropical Indian Ocean, 

 Malaysian region, Indo- 

 China and northern Aus- 

 tralia. 



lb. Nostrils much closer to eyes than to midline of snout. 



Sphyrna Rafinesque, 18 10, p. 408. 



I. For the placenta in Eusphyra blochil, see Alcock (J. Asiat. Soc. Beng., 59 [2], 1890: 52). 



