Jan Mayen Mollusca. 223 



Form rhombic, more swollen and closer ribbed than the typical 

 one. From Gray's description („Parry's Voyage", Appendix pg. 242) 

 it is impossible to recognize his species, but Dr. Jeffreys, who 

 possesses one of Gray's type-specimens aud who has seen mine, 

 regards them as identical, 



I have some hesitation in ranging this form as a species, at 

 least provisioKally I prefer to place it amongst the varieties 

 of A. sulcata. 



A series of specimens of various sizes shaws a transition to 

 A. acuticostata Jeff. (Friele, Nyt Magazin for Naturv. 1877 pag. 1) 

 for which reason I am inclined to doubt this will prove to be a 

 good species. A. acuticostata appears to be a pygmean form of 

 A. sulcata v. crcnata, assigned to the greater depths of the arc- 

 tic seas. 



Astartc lorcaJis Chem. 

 At 10 to 15 fath. 



Aainas ßcxaosus Mont. var. Goiddil Ph. 

 St. 223 aud 224 - 70 - 95 fath. 



Axinus orhicularis S. "Wood. Fig. 3 a to c. *) 



(Scacchia orhicularis Wood. Supplement to the Crag Moll, pg 124 

 PI. IX Fig. 9, KrUia orhictdaris Crag. Moll. Vo!. 2, PI. XII, Fig. 9). 



The animal white, with a large , coarse-grained lever of a 

 pale brown color, and as usual in the genus Axinus, with two 

 gills on each side; the foot long, cylindrical, but not so long and 

 filiform as in the A.flexuosus. (Fig. 3 h drawn from specimen in 

 alcohol). 



Shell white, solid, orbicular, somewhat depressed, the sculpture 

 of the mature individuals coarse concentric stripes; the young 

 ones smooth ; ligament internal, one tooth in each valve. (Fig. 3 ^ ). 

 The size 5m.m. L., 4.8 m. m. B. 



The similarity between this at Jan Mayen in shallow water 

 (10 to 15 fath.) frequently occurring form and the drawing of Searles 

 Wood Fig. 9 PI. IX in „Suppl. to the Crag Moll." is so striking 

 that I shall hardly err in considering it identical with the latter. 

 To be sure the shell of Wood's species is described as ,;Very 

 globose," while our form must rather be characterised as some- 

 what depressed, but this difference will surely prove of little sigui- 



*3 After this was printed, Prof. G. 0. Sarss «Mullusca rogionis arcticæ 

 Norvegiæ» is iiublisbed. I should think that his Axlnopsis orhiculata 

 n. gen. et sp. is the same as Axinus orhicularis. 



