790 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxiii. 



in extreme length, but .shows absolutely no characters which might 

 separate it from its smaller congeners. . Tt was first described from 

 the Miocene of Astoria; later turned up in the Pliocene of San Pedro 

 (not the Post-Pliocene, as stated by Gabb) and lastly was dredged by 

 the U. S. Fish Commission and the Young Naturalists' Society of 

 Seattle, in Puget Sound/ 



THYASIRA GOULDII Philippi (as Axinus), 1845. 



Metchigme Bay, Bering Strait, south to Sitka Harbor, the Queeji 

 Charlotte Islands, and Puget Sound, in 8 to 111 fathoms. Also on the 

 Atlantic coast and in the Pliocene of San Pedro, California, at Dead 

 Mans Island; Arnold, 



See the Atlantic list for further data, 



THYASIRA TRISINUATA d'Orbigny (as Lucina), 1845. 



Sitka Harbor, 10 fathoms; also on the Atlantic coast and the coast 

 of Korea, 



See the Atlantic list for further data, 



THYASIRA BARBARENSIS Dall (as Cryptodon), 1889. 



Coast of Washington, south to the Gulf of California, in 10 to 559 

 fathoms. 



Recalling 7\ .sy^/'.s//, but differently proportioned. The specimens 

 named A.i-inusjfexuosus by Cooper, from 120 fathoms, near Catalina 

 Island, California, proye to belong to this species,^ 



THYASIRA EXCAVATA Dall, 1901. 



Oregon to the Gulf of California in (Ui to 1,005 fathoms, 

 A well-marked species notable for the sharp Huting of the posterior 

 dorsal area. See notes and descriptions, 



THYASIRA TOMEANA Dall, 1901. 



Tome, Chile, in 10 fathoms. See notes and descriptions. 



THYASIRA MAGELLANICA Dall, 1901. 



West coast of Patagonia in lOi to 348 fathoms. See notes and 

 descriptions. 



THYASIRA FUEGIENSIS Dall (as Cryptodon), 1889. 



West coast of Patagonia and in Magellan Strait in 77 to 449 fathoms. 

 See the Atlantic list for other data. 



' It is figured in Proc. U. S. Nat. INIuseuni, XVII, 1895, pi. xxvi, tigs. 2 and 5. 

 '^It is figured in Proc. U. S. Nat. Museum, Xll, 1889, pi. viii, tig. 9. 



