54 
ACTINOPTEEYGII. 
The so-called Sjjaniodon lejjturiis (W. von der March, Palaeontogr. 
Yol. xli. 1894, p. 46, pi. v. fig. 5), from the Upper Cretaceous of 
the Baumberg, Westphalia, now in the Academy of Mlinster, does 
not belong to this genus or even to the same family. 
Genus THRISSOPTEROIDES, W. von der March. 
[Palseontogr* vol. xxii. 1873, p. 61.] 
Almost identical with Spaniodon, but the dorsal fin comparatively 
remote and opposed to the space between the pelvic and anal fins. 
The arched maxilla bearing a regular close series of minute teeth ; 
a pair of enlarged teeth at the sj^mphysial end of the mandible. 
Thrissopteroides elongatus, W. von der March. 
1873. Thrisso 2 Jteroides elongatus^ W. von der March, Palgeontogr. 
vol. xxii. p. 61, pi. ii. fig. 3. 
Type, Impression of nearly complete fish ; Academy of Munster. 
The type species, attaining a length of about 0-2. Length of 
head with opercular apparatus twice as great as the maximum 
depth of the trunk, and contained about three times in the length 
of the trunk from the pectoral arch to the base of the caudal fin. 
VertebraB approximately 70 in number, about 18 being caudal. 
Pectoral fins large, with at least 11 rays, the longest two thirds as 
long as the head with opercular apparatus; pelvic fins not more 
than half as large as the pectorals, arising considerably behind the 
middle point of the trunk; dorsal fin completel}’ opposite the space 
between the pelvic and anal fins. 
Form. Loc. Upper Cretaceous : Westphalia. 
Uot represented in the Collection. 
Thrissopteroides latus, W. von der March. 
1873. Thrissopteroides latus, W. von der March, Pal^ontogr. vol. xxii. 
p. 62, pi. ii. fig. 5. 
Type. Nearly complete fish ; Academy of Munster. 
A species about as large as the type, of comparatively stout pro¬ 
portions, the maximum depth of the trunk contained about four 
times in its length from the pectoral arch to the base of the caudal 
fin. Pectoral fins very large, with about 17 rays, the foremost 
undivided; pelvic fins about half as large as the pectorals, with 9 
rays, the foremost undivided; dorsal fin comprising 3 undivided 
