72 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxi. 



spines, behind which are traces of other spines; broad patch of prickles 

 alonj^- anterior marg-in of pectoral nearly to snout where the patch 

 becomes narrower and the prickles more scattering; scattering minute 

 prickles between and in front of eyes, and on back arranged in 3 or 4 

 rows extending- from spines about middle of back on tail to about oppo- 

 site tip of ventral; tail depressed with fold along each side and a single 

 row of stout spines along the median dorsal line from between ventrals 

 to first dorsal and one spine between dorsals; no spines on side of tail; 

 dorsal fins each with a cartilaginous support or ray similar to that in 

 Symjyterygia., not present in the other skates. 



7. SYMPTERYGIA BONAPARTII Muller and Henle. 

 BAYA. 



Sympterygia 5o?iapaW('/ Muller and Henle, Wieg. Archiv fiirNaturg., Ill, Pt. 1, 



p. 155, pi. XLix. 

 Sympterygia honapartei, Berg, Anal. Mus. Nac. Buenos Aires, IV (2d ser., I), 



1895, p. 15 (Mar del Plata; Montevideo; Rio de la Plata). 

 Symplerygia acuta Garmax, Proc. Bost. Soc. Nat. Hist., XIX, 1877, p. 206, 



Buenos Aires. 



Recorded by Berg from Mar del Plata, Montevideo and Rio de la 

 Plata. He observes that this species of ray, which is very connnon 

 in the localities mentioned and whose countr}^ was known neither to 

 Muller and Henle, nor to Giinther, is very variable in respect to the 

 prolongation of the snout, the width of the tins, the length of the tail, 

 and the shape of the antero-lateral border. This last in one example 

 is rectilinear, in other instances curved, and in others, principall}" the 

 males, sinuous. The males usually have various series of dorso-lateral 

 spines. 



In the identitication of our specimens of this genus we follow Berg, 

 although the character.'^ of the type, a female in the Berlin Museum, 

 as shown in the brief description and the figure b}^ Muller and Henle, 

 are widely difl'erent from those of our specimens. But Berg found 

 much variation in the species, and includes Garman's /S. avuta from 

 Buenos Aires (the description of which agrees fairly well with our 

 specimens) as being conspecific with his specimens. Besides, the type 

 of S. honapartu seems to be sine patria, although it is not impossible 

 that it came from South America. Miiller and Henle sa}^ that the thin 

 teeth are flat, while Garman says: "Teeth small, subquadrangular on 

 the base, sharp in the middle series, blunter to flat toward the angles 

 of the mouth, in 42 series on the upper jaw and 40 below." 



The following are descriptions of 2 of the specimens in our collection : 



Description of male: Length of disk slightly over 2 in total length; 

 width of disk 1.75; eye small, 4.5 in interorbital; snout long and 

 sharp, about 2.35 in length of disk; interorbital 3.77 in snout, wider 

 than the distance of eye and spiracle taken together. 



