FISH. 29 
This species is said by Cuvier and Valenciennes to be common all along the 
Brazilian coast as far as the mouth of the Plata. Mr. Darwin’s specimen was 
taken swimming on the surface in the Bay of Rio de Janeiro, and agrees well with 
the description by those authors. ‘‘ When first taken made a croaking noise.” —D. 
2. Prionotus Mixes. Jen. 
Puiate VI. 
P. splendid? rubro variatus ; rostro emarginato, utrinque distincté denticulato ; buccis 
levissimé granulosis ; fossuld dorsali lateribus inermibus ; squamts corporis parvis, 
ubique ciliatis ; pinnis pectoralibus modicis, corpore certé tripld brevioribus ; radius 
hiberis subincrassatis, apicibus dilatatis. 
Bez Dy 162219;- As tie Cre s&e. oP: 13iet/ 330 Vi 1/5. 
Long. unc. 10. lin. 3. 
Form.—In general form, that of the head especially, very similar to the Trigla Hirundo of the 
British seas. Compared with the P. punctatus last described, it is rather more elongated, the 
depth and thickness being less. Profile falling less obliquely. Space between the eyes broader, 
but equally concave. Snout not so obtuse, and more deeply notched ; with six short but well 
developed teeth on each side, followed by some minuter denticles. The lines of granulations on 
the snout and cheeks are very fine, and not so strongly marked, or spread over so large a portion 
of the face. One principal spine, preceded by two or three small denticles, at the anterior angle of 
each orbit ; at the posterior angle, a well marked notch with asmall denticle, (in this specimen the 
denticle on the left side of the head only,) but no regular spine : these notches are connected by a 
transverse line on the cranium, but not by a groove (as in P. Carolinus, Cuv. et Val.). No 
spines on the temples, or on the crest at the bottom of the preopercle; but the ordinary spine 
of the preopercle, as well as the opercular, suprascapular, and clavicular spines, appear as usual, 
though not quite so long as in the P. punctatus; the clavicular spine has one line of points 
along its ridge, but the granulations are not very obvious. Band of palatine teeth much as in 
P. punctatus. First dorsal spine with a row of granulated points in front; the second spine 
with a row on the left side of the fin; the third spine with a very rudimentary row on the right 
side; but none of these granulations very obvious: third spine longest, equalling about three- 
fourths of the depth of the body; the fourth and succeeding spines gradually decreasing to the 
tenth, which is barely visible, and so reclined as to be easily overlooked. Dorsal groove shallow, 
with the sides unarmed. Scales on the body small, broader than long; their free edges finely 
ciliated, communicating a decided roughness to the touch; their concealed portions crenated 
at the hinder margin, and marked with a fan of five or six strie. Lateral line not distinguished 
by any particular scales, but forming a whitish streak from the upper part of the gill-opening 
to the caudal. Pectorals relatively shorter than in P. punctatus, contained a little more thane 
three times in the entire length; when laid back they reach to a vertical line from the fourth 
