34 WOODWARD : FOSSIL FISHES OF THE UPPER LIAS OF WHITBY. 
than in the previous specimen, though this difference may be due to 
immaturity or even to the state of preservation. 
The best side of this small fossil is shown of the natural size in 
pi, iii., fig. 6. The head is almost entirely wanting, and the abdo- 
minal region is evidently a little deepened by distortion. The width 
of the caudal pedicle would originally much exceed one-third of the 
maximum depth of the trunk, and the latter measure would be 
slightly greater than one-third of the length from the pectoral arch 
to the base of the caudal fin. Nothing is seen of the axial skeleton 
of the trunk, although circumstances seem favourable to its exposure 
if it happened to be ossified. Portions of all the fins are exposed, 
except the pelvic pair, and they consist of stout rays finely sub- 
divided and closely articulated distally. Each fin is also shown to 
be provided with an anterior fringe of large, slender fulcra. The 
pectoral fin {pet.) is relatively large, with about fifteen rays which are 
undivided in their proximal half. The dorsal fin {d.) is crushed, 
but apparently as deep as long, with not less than ten or twelve rays, 
and arising opposite a point midway between the pectoral and anal 
fins. The anal (a.) is only about half as large as the dorsal. Of the 
caudal fin (c.) nothing beyond the base is preserved ; but some of the 
inferior rays are enamelled and exhibit joints longer than broad. 
The scales are preserved in patches on both sides of the fossil. They 
are all finely serrated on the hinder border as far as the posterior 
half of the caudal region, wlien they become entirely smooth, with a 
slightly concave outer face. Even the scales on the anterior part of 
the abdominal region are almost destitute of pectinations, none show- 
ing more than traces of the concentric lines of growth and a few 
punctate markings. The scales of the middle of the flank in the 
abdominal region are very imperfect, but appear to be about as broad 
as deep. A few of the displaced scales at the ventral border are 
excessively broad compared with their depth. Dorsally and on the 
caudal region, all the scales are longer than deep ; and there is evi- 
dence that the ridge-scales even at the base of the upper caudal lobe 
are not much enlarged. There are traces of the peg-and-socket 
articulation in impressions of some of the scales just in advance of 
the dorsal fin ; and the caudal scales exposed from within exhibit the 
