578 Karl A. Grönwall. 



Waagen describes this species from various parts of the middle 

 and upper Productus limestone, and Rothpletz mentions it from 

 the Permian of the Indian archipelago. 



N:o 16. Productus boliviensis D'Orb. 



For synonyms see Tschernyschew 1902, p. 250 and Wiman 1914, 

 p. 63. 



Of this species there are two specimens, both found in free-lying 

 boulders; the one at the Cape Jungersen section {N:o 120), and the 

 other at the Eskimo Naze (N:o 197), both of them being of con- 

 siderable dimensions. 



The fragment from the Cape Jungersen section is fairly well 

 preserved, and clearly shows the strong involution of the ventral 

 valve, and the sharp projecting of the ears out from the umbonal 

 part. Something is seen of the dorsal valve, too, suggesting its con- 

 cave form and the small dimensions of the visceral room. The 

 sculpture is somewhat indistinct, the shell being partially silicified. 



The other specimen is, in several respects, fragmentary. 



The species occurs in Spitzbergen, in the mosquensis limestone 

 on the Brögger peninsula, and in Beeren Eiland in the Cora lime- 

 stone. In Russia this species begins in the Cora limestone and goes 

 up into the Arta stage. 



N:o 17. Productus hiflatus M'Chesney. 



PI. XXIX, P'^igs. 17—19. 



For synonyms see Wiman, 1914, p. 66; Tschernyschew, 1902, 

 p. 261 and Stuart Weller, 1914, p. 111. 



I consider that to this species I ought to refer two specimens; 

 the one found free-lying in the Cape Jungersen section (N:o 128), 

 and the other free-lying at the Eskimo Naze {N:o 212). 



The first, the figured is a large specimen, agreeing perfectly with 

 those from Spitzbergen (Skansbay), and may specially be compared 

 with the senile specimens figured by Wiman, PI. 14, Fig. 2, and 

 PI. 15, Figs. 3, 4. Our specimen also shows the dorsal valve (which 

 however, has been displaced somewhat from its original position) 

 with its characteristic sculpture of both concentric wrinkles and 

 radiating ribs (see Tschernyschew, 1902, PI. 28, Fig. 4 c). The 

 position and form of the dorsal valve points distinctly to a high 

 visceral room. The ears are very large, so that, in our specimen 

 — which, in general dimensions, is somewhat smaller than the 

 Wiman's specimen spoken of, but which, however, is equally senile 

 in characteristics — they have attained a width, from point to point, 

 of 75—80 mm. 



