A3I1ID-E. 
mi nut us by B. Y T etter (Mittheil. k. mineral.-geol. Mas. Dresden, 
pt. iv. 1881, p. 116, pi. li. fig. 16), also seems to be referable to the 
genus Liodesmus. 
Genus MEGALURUS, Agassiz. 
[Poiss. Foss. vol. ii. pt. i. 1833, p. 13.] 
Trunk elongate, much laterally compressed. Head large ; all 
the marginal teeth large and conical, but those of the dentary 
largest; inner teeth minute; maxilla laterally compressed and 
much deepened behind; gular plate present. A ertebral centra 
completely ossified in the adult, biconcave, the hypocentra and 
pleurocentra forming distinct alternating discs in part of the caudal 
region ; ribs short and delicate. Fin-fulcra wanting. 1 Dorsal fin 
somewhat extended, but not occupying more than the middle third 
of the back ; anal fin small and short-based ; caudal fin with convex 
hinde‘r border. Scales almost oval in shape, the long axis hori¬ 
zontal. 
Megalurus lepidotus, Agassiz. 
1833-44. Megalurus lepidotus, L. Agassiz, Poiss. Foss, vol. ii. pt. i. 
p. 13 ; pt. ii. p. 146, pi. li. a. 
1839-44. Megalurus brevicostatus, L. Agassiz, ibid. pt. ii. p. 147, pi. li. 
fig. 3. [Imperfect fish ; Palaeontological Museum, Munich.] 
1851. Megalurus lepidotus , A. Wagner, Abh. k. bay. Akad. M iss., 
math.-phys. Cl. vol. vi. p. 69. 
1851. Megalurus brevicostatus , A. Wagner, ibid. vol. vi. p. 70. 
1863. Megalurus lepidotus, A. Wagner, ibid. vol. ix. p. 714. 
1863. Megalurus brevicostatus, A. Wagner, ibid. vol. ix. p. 719. 
1881. Megalurus brevicostatus, B. Vetter, Mittheil. k. mineral.-geol. 
Mus. Dresden, pt. iv. p. 116. 
Type. Nearly complete fish ; Palaeontological Museum, Munich. 
The type species, attaining a length of about 0'4. Head with 
opercular apparatus occupying nearly one-quarter of the total length 
of the fish, and the depth of the caudal pedicle contained much less 
than five times in the length from the hinder border of the oper¬ 
culum to the base of the middle caudal fin-rays. Vertebrae about 
45 in number, all much deeper than broad, smooth and not indented 
laterally. Dorsal fin comprising about 20 rays, the distance between 
its origin and the post-temporal bones about equal to that between 
1 Wagner (Abh. k. bay. Akad. Wiss., math.-phys. Cl. vol. ix. 1863, p. 717) 
describes “ feinen, borstenartigen Staeheln (fulcra) ’’ on the pelvic fins of the 
so-called M. cdtivelis. 
