4.06 



APPENDIX. 



'>^ 



equal size, forms the first ray of the anal fin, and is connected br a 

 membrane to the second ray. The ventral fin in all the three species is 

 very small : but in this it is. comparatively, the largest. IMM. Cuvier and 

 Valenciennes do not mention the particular locality from whence the 

 specimen here described from their figure was received. Equally im- 

 possible is it to determine, whether this is really the.species figured bj 

 Erown, the natural historian of Jamaica, after whom it has been named. 



PLATYSOMUS Spijcii. 

 First dorsal fin minute^ triangular^ of three connected 

 raySj the two first considerably longest ; four de- 

 tached spines behind^ but none in front of the anal. 

 Vomer Brownii. Spis and Agass. Braz. Fishes, pi. 5 ~. 



The second species I know 

 only from the figure and de- 

 scription of Spix. The first 

 dorsal fin [fig. 132 a.] is re- 

 presented of a triangular 

 shape and of three or perhaps 

 four rays, followingwhich are 

 four strong spines, but with. 

 out any membrane. The first 

 ray of the second dorsal fin is 

 not, as in our Brownii, pre- 

 ceded by a spine, but is long- 

 er than any of the others ; 

 while there are no spines either detached from, or connected to, the anal 

 fin. Thesbape of the body altogether is shorter and broader; the ven- 

 tral fin ;6' is much smaller, and placed behind, not beneath, the first dorsal 

 fin. The annexed outlines of both contours will also show that the com- 

 mencement of the anal fin is considerably behind that of the second dorsal; 

 whereas, in Brownii, it is a little in advance. 



PLATYSOMUS Micropteryx {fig. 133.) 



First dorsal fin entirely wanting^, but the back armed 

 with four isolated spines ; ventral fin hardly percep- 

 tible ; anal spines entirely wanting. 

 This third species, which I have named from the extrerae 



smalbiess of the ventral fin, which nevertheless seemed to have 



been injured, is not uncommon at Pernambuco, where the fol- 



lowmg description, and also a drawing, was executed from 



fresh specimens. 



Body remarkably thin, destitute of visible scales, and entirely silvered j 



but the back has a" bluish tinge, 



and the sides reflect pale shades 



of golden and pink ; all the fins 



are pale dusky, except the anal, 



which is yellowish. Irides vel- 



low ; margin of the head, back, 



and belly sharp ; the latter seems 



formed by a strong bone, but 



there are no external spines or 



internal tubercles ; tongue thin, 



moderate, and truncated at the 



tip ; eyes moderate ; jaws capa- 

 ble of extension, rough with 



minute and imperceptible teeth. 



