ADDENDA TO MAKSIPOBRANCIIII, ELASMOBRANCIIII, ETC. 69 
tiire of jaws, the smaller size, and the tico 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 ochraceons 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. 
Baja sayi Lesneur, Jour. Acad. Nat. Sci. Phil, i, p. 42, fig. 
Myliohatis sayi DeKay, New York Famia, Fish. p. 376. 
Tryyon sayi Miill. et Henle, Plagiostomen, p. 166. 
Myliohatis sayi, Storer, Syu. Fish. N. Amer p. 262. 
Tryyon sayi, Duiu^ril, Elasmobraiich. j). 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 bejmnd the lines of the margins. 
Veutrals 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 upiier 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 papillm at the bottom of the 
mouth, and one at each side. Body and tail naked. Color olive brown 
in adidt, reddish or yellowish in young ; lower surface whitish. This 
species closely resembles the European species jyastinaca. 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 i^osterior 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 si)ecimeus in the col- 
lection from ilew 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. 
