PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 317 



opportunity of making the correction, which, had Dr. Carpenter survived 

 to finish his work, he would undoubtedly have done himself. 



In the hurry of field-work, the specimens were confounded wrfcn young 

 T. albiiSj and hence no observations on the living animal were made. 

 Had attention been drawn to it, it might, doubtless, have been obtained 

 throughout the Aleutian chain, but no specimens occurred in the collec- 

 tions from more northern localities. Jeffreys states that the under edge 

 of the girdle and the soft parts are yellowish white, tinged with flesh 

 color ; also that littoral specimens from Herm are larger than those found 

 in deeper water. In Alaska it has been obtained only with the dredge. 



The gills occupy a space corresponding to the posterior quarter of the 

 foot; there are about eight or ten on each side. The mantle edge is 

 plain and thick. The veil is plain. The muzzle is rounded, with a little 

 papilla at the posterior corner on each side. 



Leptochiton alveclus. 



Leptochiton alveolus (Sara MS.) Loven, Ind. Molt Lit. Scaiid. p. 27, 1346. 



Not of Jeffreys, etc. . 

 LepUlopleurus alveolus G. O. Sars, Moll. Reg. Arc. Nor. p. 110, t. 7, f. 3 a-i; t. 



I, f. 7 (good), 1878. 



Hah.— Bergen, Lofoten, Finmark, 150-300 f. (Sars); Gulf of St. Law- 

 rence, in 220 fathoms, between Cape Eosier and the S. W. point of Anti- 

 costi Island, Whiteaves ! St. G eorge's Bank, Gulf of Maine, 150 fathoms, 

 IT. S. Fish Com., 1872 ! 



This extradimital species is inserted here because of its possible rela- 

 tions with the next species, and also to call attention to the addition to 

 our Xortheast American fauna made by Mr. TVhiteaves. It is a remark- 

 ably distinct species, and if typical examples had been examined by the 

 authors who have referred it to L. cancellatus, it would seem unlikely 

 that it would have been so referred. 



Leptochiton Belknapi 



Leptochiton Belknapi Dall,Proc. U. S. Nat. Mas. p. l,Jan. 18ff8. 



L. t, elongata, valde elevata, dorsaliter angulata ; albida plus minusve 

 cinereo et nigrotincta; valvis elevatis, apicibus distinctis; jnucrone cen- 

 trali eonspicuo; sculptura ut in L. alveolo, sed granulis in areis dorsalis 

 sparsiui et quincuncialiter dispositis. Yalva postica sub apice concava, 

 postice sinuata. Zona minima, spiculis tenuibus versus marginem mu- 

 nita. Lon. 10.0, Lat. 3.0 mm. Div. 00°. 



Hob.— Xorth Pacific Ocean, in lat. 53^ 08' X., Ion. 171° 19' W., at 

 a depth of 100G fathoms; black sand and shells. Brought up in the 

 sounding-cup by Capt, Geo. E. Belknap, XT. S. X., on the sounding ex- 

 pedition of IT. S. S. Tuscarora in 1874, bottom temperature 35°.5 F. 

 (Specimens obtained by H. M. S. Challenger in Balfour Bay, Royal 

 Sound, Kerguelen Id., Southern Ocean, in 20-GO fins., for examination 

 of which I am indebted to the courtesy of Bev. K. J. Boog Watson, are 

 apparently identical with Capt Belknap's specie s.) 



