300 MOLLUSKS OF BERING SEA. 



shell varies much in strength of sculpture, and in color from dark red- 

 brown to white. I therefore figure one of the original types to show 

 the range of variation. 



I would note that the second part of Vol. VII of the Am. Journal of 

 Conchology, in which my descriptions were published, was issued No- 

 vember 2, 1871, though the fourth part did not appear until 1872; 

 therefore the quotation of the species should -take the date of their 

 effective jniblication and not of the subsequent completion of the volume, 



Bela laevigata Dall. (PI. Ill, fio;. 7). 



B. larifjata Dall, 1. c, p. 98, pi. 16, fig. 7, 1871. 



This species has been identified by Prof. Sars with B. gigas Verkru- 

 zen (= arctica A. Ad. = simplex Midd. and perhaps = Defrancia BecMi 

 MoUer,* from an inspection of his type). Though the conclusions of so 

 eminent a naturalist are not to be treated lightly, 1 cannot, after study 

 of abundant material, feel entirely satisfied that the Norton Sound shell 

 is the same as the very much larger form to which it has been referred. 

 The specimens were found abundantly, were uniform in size, and pre- 

 sent every aspect of adult shells. The length of the type specimen, 

 which agrees with the others, is 7.0™™. The average length of speci- 

 mens of B. simplex or gigas, of the same number of whorls, is 0.0"'"', and 

 adult specimens are from 18-20.0™™ in length. Both forms have a mi- 

 croscopic striation, stronger in the young shells. If the two are identi- 

 cal, laevigata is rather a dwarf variety than a merely young stage of the 

 species. Between B. simplex, arctica, and gigas, allowing for the ordi- 

 nary individual variation, there is no difference whatever, and the im- 

 pression left on my mind, after examining the type specimen of B. BecMi 

 of Moller, was that it was rather an immature specimen of the same 

 species, which I noted at the time. To assist in clearing up the ques- 

 tion I give an enlarged figure of the type specimen of B. Uevigata. 



Bela albrechti Kranse. (PL IV, tig. 1). 



/). albrechti Krause, I. c, p. 27H, pi. xviii, figs. 3, 11. 



I add a figure taken from a fine Sfyecimen taken at Port Clarence, 

 Bering Strait, in 1806, having a length of 11.2™™. This is a strictly 

 arctic species. It is quite distinct from any other species. Mine are 

 pure white, with a gray-green thick epidermis. 



Bela harpa Dall. (Pi. lY, fig. 2.) 



B. harpa Dall. Proc. U. S. Nat. Mus., 18»4, p. 523. 



I add a figure of this remarkably clearly cut species, taken from the 

 type specimen 17.0 millimeters in length. The longitudinal sculpture, 

 on the whole, is more pervasive than shown in the figure, where only 

 the stronger grooves are represented. The shell has a reddish tinge, 



*Morcb (Moll. Groiil., 1875, p. 128) regards this as a variety, ventrieosa Morel), of i?. 

 violacea Mighels. But it seems to me that the rioJacea series is entirely distinct from . 

 the lavigata series. 



