944 Girard on Fishes of California. 
X. RAJIDZE. 
17. RHINOPTERA VESPERTILIO, Grrarp, Proc. Acad. Nat. Sci. Philad. 
VIII. 1856, 137. Plate XXVI, figs. 1-3. 
Description. This species is closely allied to R. javanica, 
from which it differs by the shape or outline of the head, 
which is semicircular anteriorly and very slightly emargi- 
nated, instead of being notched or concave, and by the pec- 
- toral fins, which are pointed. 
'The specimen before us measures nineteen inches and a 
half from the extremity of the snout to the tip of the tail, 
six inches and three quarters being the length of the body 
and head together. The width, from the tip of one pectoral 
fin to the other, is twelve inches. 
The cephalic region is as long as the trunk properly so 
called ; its anterior outline, as already observed, is rounded 
and but very slightly emarginated. The eyes are quite 
prominent and somewhat raised above the surface of the 
head. The lips are fringed, and the edge of the tongue 
scalloped. "The respiratory apertures, five pairs in number, 
are transversely elongated and disposed upon an open curve. 
There is a small dorsal fin situated posteriorly to the 
ventrals upon the anterior portion of the tail and followed. 
by a lanceolate horizontally flattened spine, serrated upon 
its edges. The tail is very attenuated, flagelliform, tapering 
into a filiform extremity. pepe 
The color above is of a purplish blue or slate hue, lighter 
towards the periphery than upon the dorsal region. Beneath 
dull olivaceous. 
Locality. From Tomales Bay.: 
Plate XXVI, fig. 1, represents this species seen from 
above and'somewhat reduced in size. Fig. 2, is a profile of 
the head, size of life. Fig. 3, the inferior surface of the 
_ head, exhibiting the mouth and branchial apertures, also 
size of life. | : : : 
