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 Miles. Jen. 



Plate VI. 



P. splendide rubro varialus ; rostro emarginato, utrinque distincte denticulato ; buccis 

 levissimb granulosis ; fossula dorsali lateribus inermibus ; squamis corporis parvis, 

 ubique ciliatis ; pinnis pectoralibus modicis, corpore certe tripld brevioribus ; radiis 

 liberis subincrassatis, apicibiis dilatatis. 



B. 7 ; D. 10—12 ; A. 11 ; C. 12, &c. ; P. 13 et 3; V. 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 a small 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. Carolinns, 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 striae. 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 than 

 three times in the entire length ; when laid back they reach to a vertical line from the fourth 



