300 CHROMIDES. 



snout than to that of the operculum, immediately below the upper 

 profile of the head. Scales on the cheek of moderate size, in three 

 curved series — in one specimen in two. Scales on the opercles large. 



The dorsal commences vertically above the extremity of the oper- 

 culum and terminates so close to the caudal, that the distance be- 

 tween the two fins is only one-half of the depth of the free portion 

 of the tail. The spines are rather slender and increase posteriorly 

 in length, the length of the twelfth being less than one-half of that 

 of the head. The middle of the soft dorsal and anal are prolonged 

 into a filament, extending to the end of the caudal. The soft portions 

 of the vertical fins have a slight scaly covering at the base. Anal 

 spines similar to those of the dorsal fin in length and strength. 

 Caudal rounded. Pectoral as long as the head ; ventral spine of 

 moderate size, the two outer soft rays produced into filaments. The 

 distance between the vent and the root of the ventrals equals one- 

 half of the length of the head. Root of the ventrals immediately 

 behind that of the pectorals. 



Scales ctenoid ; one of the largest covers two-thirds of the eye. 



The teeth in the jaws are small, cardiform, forming a band, those 

 of the outer series being enlarged ; the pharyngeal plate is a little 

 broader than long, armed with similar teeth, except that those on the 

 middle posteriorly are broader, molar-like. 



The colours have apparently faded. The ground-colour is a 

 reddish-olive ; six or seven dark bands traverse the body and tail, 

 that descending from the thirteenth dorsal spine being the darkest ; 

 a blackish spot at the root of the caudal. 



Length of the largest specimen 5i inches. 



8. MESONAUTA. 

 Heros, sp., Heclcel. 



Body compressed, rather elevated behind, covered with ctenoid 

 scales of moderate size. Dorsal spines numerous, anal spines eight 

 to nine ; base of the soft dorsal scaly. Teeth in a band, small, 

 conical. Anterior prominences of the first branchial arch short homy 

 processes. Cleft of the mouth small. Scales on the cheek of moderate 

 size, in three series. The origin of the ventral falls vertically a little 

 before that of the dorsal. 



Bi-azil. 



1. Mesonauta iusignis. 



Ileros insignis, Heckel, Brasil. Flms-Fische, p. 378. 



festivus, Heck. I. c. p. 376. 



Chromys (?) acora, Casteln. Anim. tioiiv. Poiss. p. 17. pi. 9. fig. 1 (bad). 

 D. j_^6_ j^ _^^_ j^ ^^^_ 27. L. transv. 4/11. 



The fold of the lower lip interrupted in the middle ; three series 

 of scales on the check. The height of the body is a little more than 

 one-half of the total length (without caudal). An oblique, straiglit 

 black band runs from the eye to the top of the soft dorsal. A black 



