A NEW GENUS OF ACANTHOPTERYGIAN . FISHES. 127 
seventeen rays, the three anterior of which are simple. The first seven exceed very 
considerably in length those which succeed them, and the fin at this point decreases sud- 
denly in height ; the remaining rays are all nearly of equal length with each other, and 
little more than one fourth of the length of the first ray. 
The ventral fins are placed rather nearer to the pectoral than to the anal. They re- 
semble the pectoral in form ; but are not quite one half of their length. Each is sup- 
ported by nine rays, the first of which is simple and slightly scabrous. 
The anus is situated a short distance behind the ventral fins, and is exactly inter- 
mediate between the pectoral and the commencement of the anal. 
The lateral line commences near the base of the anterior ray of the first dorsal fin ; 
descends gradually to the middle of the side; and is continued to the base of the 
caudal fin, Its hinder portion, and consequently the tail, is destitute of any particular 
armour. ; 
The above description is taken from the specimen first captured, which is now in 
the Museum of the Zoological Society, with occasional reference to the second spe- 
cimen (the one figured) for parts which are in the other more or less mutilated. The 
length of the original specimen, which is somewhat the largest, is nearly 5 feet. 
Between the two individuals there are some differences in the number of the teeth, 
which it is desirable to mention. The posterior series of palatine teeth, which in one 
consists of six, is extended in the other to eight on each side; and in this latter spe- 
cimen there is, on one side, a single small tooth remaining in the hinder portion of 
the palatine bone which in the first is altogether unarmed. In the lower jaw of this 
second individual the number of the smaller teeth immediately succeeding the anterior 
one is also greater than in the first, the series consisting of nine, instead of six, on 
each side. These differences may be regarded as of minor importance, and as pro- 
bably dependent on the accidental removal of some of the teeth, to which (from their 
extremely penetrating character and retral direction) these organs must be peculiarly 
liable in a fish of such ferocious habits. 
A second difference between these individuals has been already mentioned in the 
description: it seems, however, deserving of more formal notice, as it has hitherto 
been generally considered by ichthyologists that the number of the rays of the branchi- 
ostegous membrane might be regarded as offering a fixed character, even in a natural 
genus : its fixity in a species ought consequently to be looked upon as altogether un- 
questionable. In the present instance, however, the number differs in the only two 
specimens yet seen. In one there are six, and in the other seven, rays of the bran- 
chiostegous membrane. On comparison of the specimens it would seem that in the 
one which has the smallest number of rays, the deficiency occurs among the anterior 
of them, the extent of the membrane supported by its first two rays being about equal 
to that which is supported in the other by three. The occurrence is probably to be 
regarded in the light of a monstrosity merely.—E. T. B.] 
