598 
ACTINOPTEKYGII. 
small. Both paired fins present, usually well-developed. Dorsal 
fin occupying nearly the whole of the back, simple or more or less 
subdivided into two or three parts ; one or two anal fins ; caudal 
fin separate, or if united with other median fins, the dorsal with a 
separate anterior portion. Scales small and cycloid. In the recent 
forms : — air-bladder and pyloric appendages usually present ; pseudo- 
branchi® absent, or glandular and rudimentary. 
This family dates hack to the Upper Eocene, but only one extinct 
genus is recognisable. The “ cod-fishes ” and their allies of the 
present day chiefly inhabit the seas of the north temperate and 
arctic regions, often descending to great depths. Only one genus 
(Lota, Cuvier) occurs in freshwaters. 
A figure of the skeleton of Lola is published by Agassiz, Poiss. 
Foss. vol. v. pi. H. A detailed description of the osteology of Oadus 
asglejinus is given by II. St. John Brooks, Proc. Boy. Dublin Soe. 
n. s. vol. iv. (1884), pp. 166-1.96, pis. v.-ix. 
Genus NEMOPTERYX, Agassiz. 
[Poiss. Foss. vol. v. pt. i. 1844, p. 75.] 
Syn. Palceogadus, G. vom Bath, Zeitschr. deutsch. geol. Ges. vol. xi. 
1859, p. 126. 
Palceobrosmius, G. vom Bath, ibid. p. 130. 
Trunk elongated and laterally compressed, slightly tapering 
behind. Margin of jaws with a single spaced series of large, 
recurved, pointed teeth. Pectoral fins much enlarged ; pelvic tins 
small. Dorsal fin almost or completely subdivided into three 
acuminate portions, anal fin into two similar portions ; caudal fin 
separate, truncated or rounded behind. 
Nemopteryx troscheli (vom Bath). 
1836. Cyclurus era-inis, P. M. G. Egerton, Phil. Mag. vol. viii. P- dd 
(name only). . . 
1836. Cyclurus nemopteryx, P. M. G. Egerton, ibid. p. 368 (name on y)- 
1842-43. Nemopteryx crassus, L. Agassiz, Poiss. Foss. vol. v. p 
pp. 6, 75, pi. xxii. [Distorted fish ; British Museum.] 
1842-43. Nemopteryx elongatus, L. Agassiz, ibid. pp. 6, 76, pi- 
[Distorted fish ; British Museum.] 
1859. Palceogadus troschelii, G. vom Rath, Zeitschr. deutsch. geo . 
vol. xi. p. 126, pi. v. fig. 3. 
1859. Palceobrosmius elongatus, G. vom Rath, ibid. p. 130. 
1886. Nemopteryx troscheli, A. Wettstein, Fisclifauna d. Tertiaer. 1 a 
nerschief. (Denkschr. schweiz. Pal. Ges. vol. xiii.), p. 69, p • 1V • 
