30 THE NAUTILUS. 



For comparison with the other forms herein discussed, a typical 

 example is figured. 



V- bicarinata has recently been collected by Messrs. H. H. Smith 

 and A. A. Hinkley at several localities in Alabama, greatly extend- 

 ing its range towards the south. 



V. BICARINATA CONNECTANS n. V. 



Unicarinate, only the superior carina present, peripheral and basal 

 carina? obsolete, periphery rounded, base rounded or subangulated. 

 Type No. 24142, coll. Walker. Lake Michigan, New Buffalo, Mich., 

 also Lake Ontario, N. Y. Cotype in collection of L. E. Daniels, 

 LaPorte, Ind. 



Apparently of rather rare occurrence as only two specimens, wer<; 

 collected by Mr. Daniels in a considerable amount of material from 

 several localities along the south shore of Lake Michigan. A single 

 specimen also was found in a small set of V. bicarinata perdepressa 

 from Lake Ontario, N. Y., received from Mr. F. C. Baker. This 

 specimen is of special interest as illustrating the relation of this form 

 and the succeeding one. Beginning as a typical connectans, the 

 carina disappears about the beginning of the last whorl which is that 

 of a typical perdepressa. 



V. BICARINATA PERDEPRESSA n. V. PI. I, figs. 15 and 16. 



Shell broadly umbilicated, very much depressed, often planorboid. 

 Ecarinate, whorls regularly rounded, occasionally subangulated 

 around the umbilicus or at the periphery, smooth or obsoletely striate, 

 frequently obscurely malleated, especially on the lower half of the 

 whorl, very pale horn-colored, unicolored or with the apical whorls 

 more or less tinged with dull purple or red. Types (No. 24123, 

 coll. Walker) from Lake Michigan at Michigan City, Ind. Also 

 from Lake Michigan at Chicago, Ills., Millers, Ind., New Buffalo, 

 Mich., Lake Erie at Sandusky, Ohio, Lake Ontario at Jefferson 



county and ?, N. Y., and Little Lakes, N. Y. Cotypes in 



the collection of L. E. Daniels, LaPorte, Ind., and the Philadelphia 

 Academy. 



This form is very abundant along the south shore of Lake Michi- 

 gan. It would be taken for a smooth form of V. leivisii, were it not 

 for the connecting links with V. bicarinata afforded by the occasional 

 subangulated individuals and bicarinata connectans. It is very vari- 



