ADDENDA TO MARSIPOBEANCHII, ELASMOBRANCHII, ETC. 69 



tare of jaws, the smaller size, and the two cutaneous expansions. Of 

 twenty specimens the average proportional length of body and tail is as 

 four and a half to eight. In no case is the tail twice as long as the disk. 

 Color ochraceous brown ; ventral surface light. Length of body of an 

 adult male 9.4, length of tail 15, and width of pectorals 10 inches. Com- 

 mon in the rivers of Florida along the Gulf coast. Several specimens 

 in the collection were captured in Lake Monroe, at a distance from the 

 salt water, by Count Pourtales. 



DASIBATIS SAYI. 



J?rt/rt sayi Lesucur, Jour. Acacl. Nat. Sci. Phil, i, p. 42, fig. 

 MyUobatis sayi DeKay, New York Fatiua, Fish. p. 376. 

 Tnjyon sayi Mull, et Henle, Plagiostomen, p. 166. 

 Ilyliobatis sayi, Storer, Syti. Fish. N. Amer. p. 262. 

 Trygon sayi, Dumeril, Elasmobranch. p. 603. 



Disk quadrangular, about one-sixth wider than long, anterior margins 

 nearly straight, posterior and inner borders convex, outer and posterior 

 angles rounded. Snout not protruding beyond the lines of the margins. 

 Ventrals rounded. Tail strong, rather more than one and a half times 

 the length of the disk, with a strong serrated spine, bearing a short, 

 low cutaneous expansion behind the spine on the upper side, and a 

 longer, little wider one below, ending nearly opposite. Upper jaw undu- 

 lated ; lower prominent in the middle. Teeth small, smooth in young 

 and females, sharp in adult males. Three papilla? at the bottom of the 

 mouth, and one at each side. Body and tail naked. Color olive brown 

 in adult, reddish or yellowish in young ; lower surface whitish. This 

 species closely resembles the European species pastinaca. A compari- 

 son of specimens discovers the following differences: in Sayi the ante- 

 rior margins form a more blunt angle at the end of the snout, which is 

 less prominent at the apex, the outer and posterior extremities of the 

 pectorals are rounder, the posterior margins are more convex, the disk 

 is broader toward the ventrals, and the tail is longer; in pastinaca 

 the lateral and hinder angles of the pectorals and the lateral angle of 

 the veutrals are marked by blunted corners. A single small rounded 

 tubercle on the middle of the back. There are specimens in the col- 

 lection from New York, Pensacola, Bahia, and Bio Janeiro. A young 

 female measured from snout to tail 7.1, length of tail 11, and width of 

 pectorals 8.2 inches. 



