358 JOURNAL OF CONCHOLOGY, VOL. I3, NO. 12, OCTOBER, IQI^. 



Planorbis albus var. draparnaldi Beck, Planorbis rossmaessleri Anex%\^., 

 Planotbis contortus L., and Valvata piscinalis Miill., were brought ; 

 from Karesuando, visited in 1880, Vitrina angeliccB Beck, Hyalinia 

 radiatula var. petronella Charp., and a form oi Euconidus fulvus Miill. 

 The fresh-water species include the two very remarkable forms — 

 Valvata inacrostoma Steenb, and Valvata frigida Westerlund, a large 

 form o( Lifuncsa pereger var. ovata Drap., interesting examples of var. 

 acuminata Jeff., and a form of SphcErium corneum L., perhaps extreme 

 examples of the var. nucleus Stud. 



Into the question of the variation in the circumpolar forms, well 

 represented in this collection, I do not feel at present competent to 

 go, without further material, and without a closer knowledge of the 

 American species. I may, however, call attention to the Vitrina 

 angelicce Beck, and Hyalinia petronella Charp. Vitrina afigeliccB 

 differs from V. pellucida in the greater contraction of the spire, and 

 while this feature is not now considered of specific importance, yet 

 there is present a subtle difference. A similar contraction of the 

 j:pir3 will be noticed in several of these Scandinavian Helicoids, and 

 I think a common-sense view is that it is due to climate, and the 

 severe conditions during the growth periods. Hyalinia radiatula 

 Alder is here represented by three, if not four, forms. The shell 

 corresponding to our type is the one known as haninwnis Strom, so 

 labelled in this collection and in a series of shells sent by Miss 

 Esmark to Mr. Edward Collier. Then from Jarlsberg in Norway we 

 have a var. virescens, and there are representative examples from 

 Norway, Sweden, and Lapland of the beautiful large form known in 

 Scandinavia as Hyalinia petronella Charp. This shell, seen at its 

 best in the examples from Hasselfors, in Nerike, is a pure transparent 

 white, larger, with less rapidly enlarging whorls than is the case with 

 radiatula as we know it. Indeed, it is difficult' at first sight to 

 reconcile it with that species, until we call to mind the parallel in- 

 stance of cellaria Miill. and its var. conipacta Jeff. The small 

 hammonis is the later, stronger race, and the large petronella is the 

 earlier, more primitive form. 



My best thanks are due to my friends, Messrs. J. W. Taylor, Edward 

 Collier, Arthur Stelfox, and J. VV. Jackson, for help and kind sugges- 

 tions in the preparation of these notes. 



