THE NAUTILUS. 107 



The important fact revealed by these specimens shows that the 

 genus must be moved from the subfamily Hyriinte and placed in the 

 subfamily Unionince. 



Two species of Parreysia ( P. corriiguta, and P. wynegungaensis) 

 were received (numerous specimens) bearing eggs in all lour gills, as 

 in Quadrula. That these shells would be found bearing ova in all 

 four gills was prophesied as being probable by Mr. Simpson (Synop- 

 sis, page 508). 



The important bearing of this fact is that it proves that beak 

 sculpture and manner of carrying ova in the gills are not correlated. 



In this connection Mr. C. T. Simpson wrote (in a letter) several 

 years ago that gravid animals of the group of Unio (Nodularia) 

 coffer Krauss proved to carry eggs in their outer gills, and thus 

 necessitated the moving of this group from the subfamily Hyriinee, 

 genus Nodularia, to the subfamily Unioninez, genus Unio. 



But in the light, of further knowledge we see that our definition 

 of the subfamily Hyriina (as differentiated from Unionines] must be 

 amended. We must choose between beak sculpture ("radial versus 

 concentric ") or marsupial characters (" Exobranchiae versus Endo- 

 branehias") in our definitions. 



The judgment of the writer would be to drop the marsupial feature 

 and adhere to the beak sculpture, thus giving for our definition of 

 the subfamily Unionintz : ''Essentially concentric beak sculpture," 

 and for Hyriiiia: u Essentially radial beak sculpture." Thus 

 amended, the group of Nodularia coffer Krauss remains undisturbed, 

 as originally located by Mr. Simpson. 



DESCEIPTIONS OF TWO NEW AMERICAN PUPID.E. 



BY V. STERKI. 



VERTIGO NYLANDERI n. sp. 



Shell perforated, oblong, with a rather acute apex, of deep horn 

 color, pellucid; whorls 4^-5, quite convex, with a deep suture, with 

 sub-regular, crowded striae (except the embryonal), the last occupy- 

 ing about one-half of the altitude, gradually narrowed towards the 

 aperture, which is small; peristome slightly everted, margin not 

 thickened; palatal wall with an indentation barely above its middle, 

 forming a well-marked sinus and sinulus; behind it a trace of a crest, 

 and behind that a long, deep furrow-like impression over the palatal 



