12 
trunk, and arc thus directly transverse on the tiank-sealcs, v.diile more or less 
oblique on the equilateral scales dorsally and ventrally. The lateral line 
produces no external ridge, but the largo canal, filled Avith ferruginous 
material, is conspicuous in the original of PI. Ill, Pig. d. 
Apiinelepis, sp. 
Plate III, Pig. .5. 
One fragmentary specimen, in counterpart, proves that Aphtielepts 
sometimes attained tivice the size of the tishes just described ; but there is as 
yet no means of determining Avhether this fossil is specifically distinct from 
A. australis or Avhethcr it merely represents a gigantic individual. The dorsal 
tin and some of the scales are shoAvn of the natural size in PI. Ill, Pio-. 5. 
8o far as can be ascertained, the tin agrees Avith the dorsal of A. australis in 
all essential respects ; and there is nothing Avorthy of remark in the sqiiania- 
tion, except that the posterior denticles of the dorsal scales are especially 
prominent. It is, hoAVCver, interesting to note that there arc undoubted 
remains of Avell-developixl ribs. 
AETIIEOLEPIS, yen. nor. 
Gen. Char. — Trunk deep and laterally compressed ; head small, and 
external bones more or less tuberculated. Notochord ])ersistent, apparently 
Avithout ossitications in the sheath. Pin-rays robust, all branched and closely 
articulated distally, but simple in the proximal portion; fulcra A\xdl dcA'elopcd. 
Pectoral fins placed laterally; pehde tins of moderate size; dorsal and anal 
lins much extended, acuminate in front, and both remotely situated; [? caudal 
tin not forked]. Scales of abdominal region thick, much deepen’ than broad 
on the Hank, quadrate in form, moderately overlapping, Avith large peg-and- 
socket articulation and an anterior inner longitudinal keel, the scales of this 
form gradually passing into those of the caudal region, Avhich arc A'cry thin, 
dec})ly imbricating, and more or less oval in shape. Scalc-ornamcnt consisting 
of tubercles. 
AeTIIEOLEPIS AIIEABILIS, Sp. HOC. 
Plate III, Pig. 0 ; Plate IV, Pigs. 1-7. 
Ohs. — The materials iq)on Avhich this genus and s])ccies are based, 
clearly exhibit all the more important characters of the tlsli, except the 
dentition and the extremity of the caudal lin. They comprise the folloAA’ing 
t 
specimens : — 
(«) The type specimen, partly preserved in counterpart, and shoAvii of 
the natural size in PI. IV, Pig. 1. 
