10. CARCHARIID^: - CAHCHARIAS. 27 



24. AL.OPIAS Rafinesqiio, 1810. 



Thresher Sharks. 

 (Alopecias M tiller & Hciilo; corrected orthography.) 



(Rafiuesqne, Carattcri di Alcuiii N. Generi, etc. : type Alopias macroiinis Raf. Squalus 

 ritlpes Gmeliii.) 



The characters of the genus are included above. (rUw-o-, a fox; 

 Latin, pitlpes. A. vulpes was known to the ancients as a/.iu-^/.iaq = fox-like.) 



33. A. Vlllpes (Gmel. ) Bonap. Thresher; Fox-Shark; Swingle-tall; Long-tail Shark. 



A large shark, abounding in all warm seas, especially in the Mediter- 

 ranean and Atlantic. It is also occasionally taken on our Pacific coast. 

 Known at once by the great length of the tail. 



(Squalus culpes Gmelin, Linn. Syst. Nat. i, p. 496 ; Alopecias culpi 1 * Giinther, viii, 39.'?.) 



FAMILY X. CARCHARIID^E. 



(The Sand Shark*.) 



Body rather elongate, the snout sharp ; mouth crescent-shaped, wide; 

 the teeth large, long, and narrow, subulate, most of them with one or 

 two small cusps at the base, their edges entire; gill-openings rather 

 large, all of them in front of the pectorals ; two dorsals, moderate, sub- 

 equal, the anal similar ; fins, dorsal well behind pectorals ; caudal well 

 developed, with a short basal lobe and a notch toward its tip ; no caudal 

 keel ; pectorals rather short ; no nictitating membrane ; spiracles minute, 

 pore-like. Genera 1 or 2, Carcharias Eaf. ( = Odontaspis Ag. ; not Car- 

 charias C\iv. = Carcharinus) and u Eugomplio&m'" ] species 3. Voracious 

 sharks of moderate size, chiefly inhabiting the Atlantic. (Lamnidce, part, 

 Giinther, viii, 302 ; genus Odoutaspis.) 



* Teeth large, awl-shaped, all or nearly all of them with one or two small cusps at the 

 base .......................................................... CARCHARIAS, 25. 



25. CARCHARIAS Rannesque, 1810. 

 Sand Sharks. 



is Agassiz.) 



(Ranuesque, Caratteri di Alcuui Nuovi Geueri, etc. : type, and only species mentioned, 

 Carcharias taunts Raf.) 



Characters of the genus included above, (zripxapo*;, rough.) 



* First and fourth teeth of the upper jaw and first tooth of the lower simple, with- 

 out basal cusps. (Eitf/omjihodus Gill.) 



34. C. amcriCilBllls (Mitch.) Jor. & Gilb. Sand Shark; Shorcl-nose. 



Body elongate, its depth one fifth the length ; head rather pointed, 

 about one seventh of the length ; fins small, the first dorsal not much 



