338 
ACTINOPTEUYGII. 
Bugey, pt. ii. p. 17, pi. xii. fig. 1. [Nearly complete fish ; Lyons 
Museum.] 
1881. u Caturus ” segusianus , B. Vetter, Mittheil. k. mineral.-geol. Mus. 
Dresden, pt. iv. p. 110. 
Type. Nearly complete fish ; Lyons Museum. 
A large species, attaining a length of about 05. Length of head 
with opercular apparatus about equal to the maximum depth of the 
trunk, and less than one-quarter of the total length of the fish. 
Caudal region tapering to a comparatively slender pedicle, its depth 
equalling about one-third the maximum depth of the abdominal 
region. Teeth smaller than in the type species. Dorsal fin deeper 
than long, and its depth nearly or quite equalling that of the trunk 
at its origin ; this fin arising well in advance of the middle of the 
back, the distance from the occiput to its origin being considerably 
less than that from its hinder border to the base of the caudal fin. 
Pelvic fins arising opposite the hinder half of the dorsal fin ; anal 
fin much smaller than the dorsal; lobes of the caudal fin especially 
slender. Scales larger than in the type species, smooth. 
The peg-and-socket articulation of the scales indicated in 
Thiolliere’s figure, is not shown in the specimens enumerated 
below. 
Form. Sf Loc. Lower Kimmeridgian (Lithographic Stone) : Ain, 
Prance. 
P. 905. Pine large specimen ; Cirin. Egerton Coll. 
P. 4700. Smaller and more imperfect specimen, the trunk shown 
chiefly in impression ; Cirin. Purchased, 1884. 
P. 4697-8. Two imperfect large specimens about 0-54 in length, 
for the most part shown only in impression, probably of 
this species ; Cirin. Purchased, 1884. 
Caturus velifer, Thiolliere. 
1850. Caturus velifer, V. Thiolliere, Ann. Sci. Phys. & Nat. Lyon, [2] 
vol. iii. p. 143. 
1873. Caturus velifer, V. Thiolliere, Poiss. Foss. Bugey, pt. ii. p. 17, 
pi. xii. fig. 2. 
1881. “ Caturus ” velifer , B. Vetter, Mittheil. k. mineral.-geol. Mus. 
Dresden, pt. iv. p. 110. 
Type. Nearly complete fish ; Lyons Museum. 
A large species, closely related to C. driani, but distinguished by 
its more elongated trunk, the length of the head with opercular 
apparatus exceeding the maximum depth of the trunk, and the 
