66 CONTRIBUTIONS TO NORTH ^ AMERICxiN ICHTHYOLOGY IV. 
Dasibatis TUBEKCULATA. 
Jloja tuhercniafa Lac^p. ii, p. 106, pi. 4, fig. 1. 
Jiaja tiihcrculata Shaw, Geii. Zofil. v, pt. 2, p. 290, pi. 127. 
Trygon gumnura Miill. Erinan’s Reise um die Erde, ii. 25, Taf. 13. 
Trggon ostimticta Miill. 1. c. p. 25,\'af. 14. 
Trggori tuberciilata Dnmeril, Elasmobr. p. 605. 
Trggon tuberciilata Gunther, Cat. viii, p. 4S0. 
Bisk qaadrangular, a little wider than long. Snout produced, sharp 
pointed. Anterior aud posterior margins nearly straight, the anterior 
curved near the outer angle to meet the posterior, and the latter curved 
near the hinder angle to meet the inner. Tail nearly three times the 
length of the disk, with a slight ridge above aud a narrow cutaneous 
expansion below, roughened witli small spines similar to those on the 
head, bearing a long serrated spine. A row of elongated tubercles on 
the dorsum and anterior iiortion of tail and one or more smaller ones on 
each shoulder. The iiosterior tubercles of the median row are so much 
elongated as to resemble the spine. Mouth much undulated, with three 
l)apillie. Teeth small, unequal. Color yellowish to olivaceous brown, 
darkening with age. The young are without scales or tubercles. As 
the animal grows older and the tubercles appear a few scattered asperi- 
ties appear on the head ; still later these increase in number and size to 
such an extent as to cover the head and dorsum with a heavy coat of 
mail made up of the closely-set flattened scales. The tubercles of the 
back cease growung as the scales enlarge, aud ultimately there is little 
distinction between them. Usually the tubercle on the middle of the 
pectoral arch is larger ; those on the tail continue to increase in size 
with age. A young female measures in length of body 9.9, length of 
tail 28.2, and width of disk ll.G inches. 
Cannavierias, Surinam, Para, Bahia, and Eio Janeiro. 
BASIBATIS LONGA. 
(Garman, 1880, Bull. Mas. Corap. Zool. vi, p. 170.) 
Bisk quadrangular, about one-sixth wider than long. Margins nearl^^ 
straight, anterior meeting in a blunt angle on the end of the snout. 
Outer angles rounded, posterior blunt. A'^entrals rounded. Tail more 
than twice as long as the body, roughened with small asperities, de- 
l)ressed anteriorly, compressed behind the spine, keeled above the com- 
])ressed portion, with a long, narrow cutaneous expansion on the lower 
side. Mouth curved with five papilla). A row of small tubercles behind 
the head on the shoulder girdle. It is likely that larger specimens are 
provided with tubercles on back and tail. 
