PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 37 
Mouth broad, its width equal to the distance from its front margin 
to the tip of the snout; a deep crease passing around the mouth 
behind, in front of which the lower lip has three folds of skin. Upper 
lip not developed, a strong fold of skin passing from the angle of the 
mouth on either side to the inner angle of the nostrils, thence straight 
across, joining its fellow on the opposite side, these folds enclos- 
ing a depressed, subtriangular, J \ shaped area, Which is bounded 
behind by the curved outline of the upper jaw. In this depression are 
three transverse cross-folds of skin. Nostrils broader than the interval 
between them, with a free fold behind, which is prolonged forwards and 
inwards in the middle, the rest of the fold being turned backward. An- 
terior edge of nostrils with a broad flap, the outer edge of which is much 
prolonged, overlapping the posterior flap, the inner edge covering the 
inner angle of the nostril. 
Both jaws strongly and somewhat regularly curved. Teeth numerous, 
rather sharp, about £2, about twelve in 2 cross-series. Gillopenings very 
narrow. 
Skin everywhere covered with arather fine shagreen, almost precisely 
as in Rhinobatus productus. The asperities are smaller below, and 
coarser on the outer anterior margin of the pectorals, where there are 
also two or three irregular rows of sharp, curved, backward-directed 
spines. Four strong spines on the tip of the snout, forming a rhombic 
figure ; four or five strong, bluntish spines around each eye, above and 
in front, the one at the upper anterior angle the largest. 
A series of 22 very strong spines along the median line of the back 
and tail, and two more on the tail between the dorsal fins. On each 
side of the tail above is a similar series of ten spines, the first opposite 
the end of the base of the ventrals, the last opposite the front of the 
first dorsal; a single strong spine on the outer edge of the shoulder-gir- 
dle and two between the spine and the dorsal series. 
Color almost exactly as in Rhinobatus productus. Olive-brown above, 
whitish beneath, the vertical fins paler. Rostra] area and edges of pec- 
torals somewhat translucent. No sharp markings of any kind anywhere. 
Measurements. 
Mee OMG eae (sos a 32 3) oao ace ioc se celncnmiecesoeae.s-o-> 17,90 mnehes; 
Em Ol Gse= ss) eis Safe tivicies sas) a aelmaeast-= Mose) f. coches — 12500 
0 ae ie eee eNOS aes ge ee es Oe = Pn oe ee eer 1. 09 
urimca all ali Dasek-maau es a5 Sek hs Ae ae aaiomin aaa eae = oselmmel oc Se,= =~ . 20 
Mistance between outer humeral spines ~.2. ----.--=-=-2--,--+-s2-=s6 c-+0--2- - 36 
pecan bnranrClival EEA) 5.) = (32 2. 2)paania' a oo ea mao Sapien - oe ee aa neon <2 ~15 
mma branehiat hepaam front. 22225224. --52.s22-02t--2-- Sele senweens -- 2. 34 
emer Dranchial\area behind :.:.. izes. 22+... -2- -s25-s nce s-25-- --0--- 28 
Distance between outer edges of nostrils....-...-..---------- EEO ie ih . 21 
RITES Te ete oe ee cpa tenia a's aim rn iSinimein ce wee oes . 20 
SMEMIMITTECEON ial) ATOM. =) 22-522 qdenn cones n- nek lee~ ee ne se fons -- + anes . 165 
2S Sul go oe Ae ed Se ee ee ee ee ee . 06 
Length of snout from eye ..-.-......-- LIN TG ST 2 Sea ae i 295 
