98 DEAN. [Vor. IX. 
protruding from the body wall ; the arrangement of the basalia, 
moreover, gives ample ground for regarding a girdle as lacking. 
That Cladoselache is by no means of a modern order of 
shark Jaekel, himself, has already given one and a very 
convincing proof, in describing the circum-orbital ring of derm 
plates, whose acanthodian value might at once have led to 
a closer scrutiny of fin characters. A final and positive 
proof as to the claims of this fish to archaic characters is 
now at hand in the unique structure of the caudal. Jaekel 
has several times referred to the “painted tails” of the older 
specimens, figured by Newberry ; these now prove, from an 
examination of a number of examples, to have been in no 
way falsely restored —if restored they had ever been — by 
their collector. The spade-like body terminal, as it was 
originally figured, appears now to have represented a vertical 
projection, whose tapering apex represented a portion of the 
margin of the tail. The length of the specimens (which 
Jaekel states should be considerably greater) proves to be 
exactly as Newberry described it. 
THE CAUDAL OF CLADOSELACHE. 
The structure of the caudal was a remarkable one, —its 
characters strongly suggestive of Acanthodes. The noto- 
chord extends to the tip of the upper lobe in the usual 
elasmobranch manner, but is so sharply upturned that the tail 
has become widely vertical (Fig. 3). So broadly have the 
lobes forked that the tail outline has become that of Xiphias ; 
its total breadth equals the measurement from tip to tip 
of the pectorals. Its posterior margin is not, however, an 
indented one ; it forms a straight line at right angles with the 
axis of the fish. 
Structurally, the remarkable character of the fin is that 
the upper lobe is strengthened only on the neural side, it is 
wanting in hypural rays, and is in this region web-like. 
Epurally it is supported by a prominent cut-water of well- 
defined cartilages. 
In hypural characters the caudal structures may well be 
compared with those of Acanthodes; there is a series of 
