PERCOIDE.E. 7 



margin producing two thin points : the lower point is closely applied to the apex of the sub- 

 operculum, forming with it one thin obtuse plate, which, together with the upper point, are 

 concealed by the membrane which borders them. The under margin of the suboperculum is 

 slightly waved, forming two obscure lobes. As in many, or perhaps in most, of the pereoideae 

 with scaly gill-covers, the margins of the pieces composing them are covered with smooth 

 skin : there is even a wider naked space than usual behind the points of the operculum, and 

 the anterior border of that bone is as wide and prominent as the limb of the preoperculum to 

 which it adjoins. The forehead, snout, infra-orbitar bones, and margins of the orbits, man- 

 dibles, labials, branchiostegous membranes and edges of the different opercular bones, are 

 covered with smooth skin ; the rest of the head, including the temples and top of the cranium 

 as far as the linea rostri basalis*, are clothed with tiled scales. The bones lining the posterior 

 edge of the gill-openings are likewise scaleless, and their edges, though undulated, are des- 

 titute of spines or serratures. The nape is supported by a median ridge of the cranium, and 

 a thin lateral one on each side equally high. There are also several inter-spinous bones 

 anterior to the first dorsal. The Branchiostegous membrane contains six curved rays, the 

 anterior ones cylindrical, the posterior ones becoming more and more flat and wider. 



Fins.— Br. 6; D. 6/ — 2/8 ? ; P. 15; V. 1/5; A. 3/11 ; C. 17|. 



The pectorals consist of fifteen rays, the first of which is short, and its articulations very 

 obscure, being visible only at the tip and with a lens. The ventrals are attached directly 

 under the pectorals, and contain six rays, of which the first is spinous and one-third shorter 

 than the succeeding ones. The first dorsal consists of six acute spinous rays, having the 

 connecting membrane notched between them : the first ray is one-third shorter than the third, 

 which is the longest, and stands about an inch behind the insertions of the pectorals and 

 ventrals : the fourth and fifth are nearly as long as the third. The second dorsal is one-third 

 higher than the first, and commences nearly an inch behind the posterior insertion of the 

 membrane of the latter : the two anterior rays are spinous and separated by membrane, — 

 the first of them equal in height to the corresponding ray of the first dorsal : the third ray is 

 simple but articulated ; the succeeding ones are branched at the tips, and nearly equal to 

 each other, the seventh being, however, rather the highest : the fifth ray is opposite to the anus, 

 and the tenth (it is not certain whether this be the last or not, as the specimen is injured) is 

 opposite to the fifth of the anal. The anal contains fifteen rays, the two first of them shorter, 

 spinous, and very acute : the branched rays equal those of the dorsal in height. : the first 

 spinous ray stands half an inch behind the anus. If the fish, exclusive of the caudal-fin, be 

 divided into three parts, the head will form one, and the first spine of the anal will stand at 

 the commencement of the third. The space between the anal and caudal considerably exceeds 

 that occupied by the attachment of the former. The caudal is somewhat rounded and very 

 slightly emarginated : its base is covered with small scales, which terminate by an even line 

 rounded off on the three exterior rays, while they cover the accessory short rays, above and 

 below, to their tips, thus producing a notch at each end of the line. 



Scales. — The scales are rather large, the exterior edge forming a segment of a circle and 



* Linea rostri basalts ilia est, quw per marginem orbilce posleriorem Iransversim dneitur. — Nii.sson. 



