164 WOODWARD : FOSSIL FISHES OF THE UPPER LIAS OF WHITBY. 
obscure. The squamation is only imperfectly preserved, and the 
enlarged anal scale is fragmentary. 
The fish just described is of the form named P. graciHii by 
Agassiz, as is indicated by a specimen in the Enniskillen Collection 
(No. P. 37 11) bearing his label, and by another in the Egerton 
Collection (No. P.885), of which he signed the label. The first of 
these specimens is much elongated by crushing, while the other is 
similarly deepened ; but they appear to agree with P. curtus in all 
characters which can be compared. The operculum of No. P.3711 is 
shown to be triangular in shape and slightly deeper than broad ; 
both exhibit delicate ribs, and the second also free neural spines in 
the abdominal region. These neural spines, however, are better seen 
in another specimen in the British Museum (No. P. '2037), which seems 
to show also free atrophied fin-supports above them 
The type specimen of the so-called Pachijcormus latus in the 
Enniskillen Collection (Brit. Mus., No. P.3699) is too imperfect for 
determination, but seems to represent merely a large individual of 
P. curtits, nearly twice as large as the ordinary individuals of the 
latter. It is curiously restored after the manner of the Whitby 
dealers, the counterpart of the pectoral fin being fixed above the 
head, and other fragments of the counterpart being worked into the 
lower portion of the caudal region. It wants the end of the snout 
and the anal and caudal fins. The dorsal fin is also very imperfect. 
The remains of the head and opercular apparatus suggest the pro- 
portions of P. curtus, and the scales appear remarkably large because 
they are scattered and not in their regular overlapping sequence. 
The comparatively upright direction of the neural spines in the front 
half of the caudal region probably implies deepening of the trunk by 
distortion. 
The original description of the type specimen of Pachycormus 
curtus being in some respects misleading, as already remarked, it is 
not surprising that the species has been misunderstood, while French 
Upper Liassic specimens, which most likely belong to it, have 
received distinct names."'' The classification of the species of 
* H. E. Sauvage, Bibl. Ecole Hautes Etudes, vol. xiv. (1875,, No. 1, 
and Bull. Soc. Sci. Yonne [3], vol. vii. (1883), pp. 41-46, pi. ii. 
