PLIOCENE AND PLEISTOCENE FOSSILS FROM ALASKA. 



31 



second beacli. Collected by E. M. Kindle and 

 R. D. Mesler, 1908. U. S. Nat. Mus. catalogue 

 No. 324301. 



This species, from fragmentary remains col- 

 lected by J. J. V. Beaver, of Nome, was iden- 

 tified by me in 1907,^ with P. (C.) swifii Ber- 

 nardi, of northern Japan. The present much 

 more complete material, obtained the followmg 

 year, enables me to correct this identification. 

 The shell indeed much resembles the Japanese 

 form, but it has not the concentric waves due 

 to resting stages that appear in P. swifti, and 

 the posterior ear is of quite different shape. 

 The two bear to one another much such a rela- 

 tion as is found between Peden nodosus of the 

 Antilles and P. suhnodosus of the Pacific coast 

 of America. 



Related to this species is the P. 'parmeleei Dall 

 from the Pliocene of San Diego, Calif., with 

 which fragments from a Pliocene deposit near 

 Crescent City, Calif., were identified. The 

 latter (figured by Arnold^) upon later and more 

 exact study prove to be indistinguishable from 

 the true P. swifti of Japan. The minute 

 structure of the reticulated outer layer of P. 

 parmeleei is quite distinct from that of P. 

 swifti or the present species, but this delicate 

 structure is so rarely preserved intact in the 

 fossils that its help in specific discrimination is 

 seldom available. 



Pecten (Chlamys) lioicus Dall. 



Pecten {Chlamys) lioicus Dall, Am. Jour. Sci., 4th ser., 

 vol. 23, p. 457, fig. 1, 1907. 



Frora 50 feet below the siu'face in marine 

 gravels near Nome, Norton Sound, Alaska, 

 from a collection received by F. H. Moffit 

 from Mr. J. J. V. Beaver, of Nome ; donated 

 to the U. S. Geological Survey. U. S. Nat. 

 Mus. catalogue No. 110480. Phocene. 



No further specimens of this very distinct 

 species have come to hand. 



Pecten (Chlamys) n. sp. 



In the material from the dumj) of an 80-foot 

 shaft about a mile north of Nome (station 7477) 

 were fragments of a Pecie?i undoubtedly distinct 

 from any known northeastern Pacific species, 

 but insufficiently complete to warrant naming. 

 The ribs are high, with wider channeled inter- 



1 Am. Jour. Sci., 4th ser., vol. 23, p. 457, 1907. 



2 Arnold, Ralph, The Tertiary and Quaternary pectens of California: 

 XT. S. Geol. Survey Prof. Paper 47, pi. 41, figs. 5, 5a, 1906. 



spaces. On the back of the ribs in the middle 

 of the valve is a strong radial cord on each side 

 of which is a smaller cord separated from the 

 median one by a narrow groove. The mox"e 

 lateral ribs have a groove between two mod- 

 erately strong cords, the inner cord of the 

 medial ribs becoming obsolete. The ribs bear 

 small low imbricating scales. In the inter- 

 spaces the fine sculpture is minutely tessellate, 

 the alternate scales sometimes raised, giving a 

 minutely pustular effect. The medial ribs 

 are about 3 milhmeters and the mterspaces 

 about 4 millimeters wide. The submargins 

 are feebly and more numerously threaded. 

 The interior is smooth, grooved m harmony 

 with the external sculpture. The shell prob- 

 ably reaches a length of some 3 inches when 



adult. 



Astarte actis Dall, n. sp. 



Plate VI, figures 4, 5. 



Shell of moderate size, roimded, very thick, 

 nearly equilateral, beaks rather pointed, not 

 conspicuous, usually more or less eroded ; limule 

 lanceolate, narrow, elongate, shallow; ligamen- 

 tary nymph strong, the nearly linear escutcheon 

 extending beyond it 3 or 4 millimeters; outer 

 surface rather rudely sculptured with coarse 

 concentric incremental lines; hinge extremely 

 heavy, in the right valve a strong thick cardinal 

 with deep pits on each side to receive the two 

 narrower cardinals of the left valve, the pos- 

 terior of which is more or less radially furrowed ; 

 there are traces of an obsolete anterior lateral 

 in the left valve and of a receptacle for it in the 

 right valve which vary in distinctness with the 

 individual specimen ; impressions of the adduc- 

 tors and mantle attachment are usually deep 

 and distinct; the inner margins of the valves 

 are entire. Height, 33 milhmeters; length, 36 

 milhmeters ; diameter, 20 millimeters. 



Station 5074 (18a). Pliocene on Center 

 Creek, about half a mile north of Nome, from 

 the second beach; collected by E. M. Kuidle. 

 U. S. Nat. Mus. catalogue No. 324302. Also 

 station 7619 (ISa), Center Creek mines, 2 miles 

 northwest of Nome; collected by E. M. Kindle 

 and R. D. Mesler, 1908. 



Astarte carteriana Dall, n. sp. 



Plate VI, figures 1, 3. 



Shell of moderate size, rather mflated, the 

 general profile like Saxidomus giganteus on a 

 small scale; surface sculptured with rather 



