TRIASSIC FISHES FROM SPITZBERGEN 
203 
(1918 b, loc. cit.) were all four found at the fish horizon. The .three first-mentioned 
specimens come from Mt. Congress; the Christiania specimen was found in the steep 
shore below the Swedish station at Cape Thordsen. 
Genus Pygopterus Agassiz. 
Synonym: Myriolepis? Woodward, A. S. Upsala, Geol. Inst., Bull. vol. XI, p. 293, 1912. 
The genus Pygopterus was founded in i 833 by Agassiz (i 833 , vol. II, part 1, p. 10; 
1844, vol. II, part 2, p. 74), and after him several authors have studied it more or less 
in detail. Among these we may specially mention Egerton, who published fine figures 
of his material (1850, pp. 232—234; Pis. 23 , 24), Traquair, who undertook a thorough 
revision of the species of the genus described up to 1877 (1877 b, pp. 572—578), and 
Woodward, who in 1891 (1891 b, pp. 470—475) gave a short description of the mate¬ 
rial of the British Museum and at the same time gave a detailed list of synonyms and 
a list of the earlier literature. 
Traquair’s revision caused the genus Pygopterus to be restricted to the Permian 
formation. For a long time it was really only known from the upper part of this 
formation in England, Russia (Krotov 1904, pp. 3 o— 3 i) and Germany. 1 ) Now, however, 
according to Deecke (igi 3 , p. 77) it has also been found in the upper part of the bunter 
Sandstone of Germany (cf. Stolley 1920, p. 81) and, according to the material at my 
disposal, it seems also to occur in the lower part of the Triassic at Spitzbergen, where, 
as far as is known, it is represented by a single species. An incomplete and very much 
crushed specimen of this species is mentioned by Woodward 1912 (p. 2g3) and put by 
him, though with much hesitation, under the generic name Myriolepis. 
My fresh material from Spitzbergen can scarcely increase our knowledge of this 
genus to any great extent, and I am therefore' unable to give any more complete definition 
of it than that formulated by Woodward 1891 (1891b, p. 470), which I consider it super¬ 
fluous to repeat here. 
Pygopterus de geeri n. sp. 
(PI. 25, fig. 3; PL 26, figs. 1, 2; PL 27, fig. I.) 
Synonym: Myriolepis ? sp. Woodward, A. S., Upsala, Geol. Inst. Bull., vol. XI, p. 293, 1912. 
The material on which I have based the species Pygopterus de geeri consists of six 
incomplete specimens (P. 106, P. iog — 112, P. 671c). 
That this species attained a comparatively large size is shown by the specimen 
investigated by Woodward in 1912 (P. m), in which the height of the body just behind 
the head was about 11 cm. A couple of other specimens (P. iog, P. 112) seem to have 
attained the same or almost the same size. The smallest specimen present (P. 671 c) has 
its body 4 cm high just behind the head. 
The shape of the body seems apparently to have been fairly elongated and the 
head relatively short, its length being probably little more than about a fifth of the 
total length of the animal. 
J ) The type-specimen for the so-called Pygopterus bonardii Agassiz (Agassiz i 833, vol. II, part. 2, p. 11) 
from the lower Permian of Autun was in 1890 described and figured by Sauvage (1890, pp. 25—26; Pl. IV, 
fig. 1). According to Sauvage this species undoubtedly would belong to Pygopterus. Neither his description nor 
his figure, however, give any definite proof for the correctness of his opinion. 
