PACHYC0RMID2E. 
385 
P. 3705 a, b, e, P. 3710 c. Four similar specimens ; Whitby. 
Enniskillen Coll. 
P. 884 f, P. 3703. Another head, in counterpart ; Whitby. 
Egerton Enniskillen Colls. 
P. 3705 d. Portion of opercular apparatus and anterior squamation ; 
Whitby. Enniskillen Coll. 
Pachycormus curtus, Agassiz. 
1832. Urceus gracilis, L. Agassiz, Neues Jahrb. p. 142. 
1833-44. Pachycormus gracilis, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 
p. 12; pt. ii. p. 114 (undefined). 
1844. Pachycormus curtus, L. Agassiz, ibid. pt. ii. p. 112, pi*, lix. 
1844. Pachycormus latus, L. Agassiz, ibid. pt. ii. p. 114. [Portion of 
fish ; British Museum.] 
1843. Pachycormus curtus , F. A. Quenstedt, Flozgeb. Wiirttemb. p. 244. 
1858. Pachycormus curtus, F. A. Quenstedt, Der Jura, p. 235, pi. xxxii. 
fio% 4. 
1860. Pachycormus curtus , A. Wagner, Gelehrte Anzeig. k. bay. Akad. 
Wiss. vol. 1. p. 225. 
Type. Nearly complete fish ; British Museum. 
A stout species of moderate size, attaining a length of about 0*5. 
Head much shorter than in the type species, and this with the oper¬ 
cular apparatus occupying more than one-quarter of the total length of 
the fish; operculum triangular, deeper than broad, and branchiostegal 
rays about 40 in number. Scales of moderate size and smooth. 
Variously crushed examples of Pachycormus from the Upper Lias 
of the Dept. Tonne, France, not yet clearly defined and distinguished 
from P. curtus , have received the names of Caturus stenospondylus 
(H. E. Sauvage, Bibl. Ecole Hautes Etudes, vol. xiv. 1875, no. 1. 
p. 13, pi. iii.; Bull. Soc. Sci. Tonne, [3] vol. vii. 1883, p. 41; and 
Bull. Soc. Hist. Nat. Autun, vol. iv. 1891, p. 75) ; Caturus stenoura 
(H. E. Sauvage, loc. cit. 1875, p. 18, pi. i. fig. 2 ; Joe. cit. 1883, p. 46, 
pi. ii. fig. 2; and loc. cit. 1891, pp. 78, 81, pi. viii.) ; and Caturus 
chaperi (H. E. Sauvage, loc. cit. 1883, p. 43, pi. ii. fig. 1; and loc. 
cit. 1891, p. 76, pi. vi.). Another fish from the Upper Lias of 
Werther, Eavensberg, Westphalia, also not clearly distinguished from 
P.curfr<s(and thus provisional^ determined by F. A.Boemer,Yerstein, 
norddeutsch. Oolithen-geb., Nachtr. 1839, p. 53), is named P. crassus 
(A. Wagner, Gelehrte Anzeig. k. bay. Akad. Wiss. vol. 1. 1860, 
p. 226). Here also may perhaps be placed the undefined Caturus 
meyeri (L. Agassiz, ex Munster MS., Poiss. Foss. vol. ii. 1844, 
p. 118) from Werther. 
Form. § Loc. Upper Lias: Torkshire, Gloucestershire, and 
Somersetshire; N. France ; Wiirtemberg. 
2 c 
PART Til, 
