26 Remarks on Classifications of 



several years ago called my attention to it. He sent me a plate 

 (executed under his direction), in which it is figured with II 

 clausa, Mitchelliana, Pennsylvania, and Columbiana. It 

 appears in form more like, but smaller, than Pennsylvania, 

 having a somewhat similarly shaped aperture, without, how- 

 ever, the callosity on the lower margin of the lip ; the umbi- 

 licus partially open. I have seen no specimen agreeing with 

 the figures. 



After arranging a series of typical specimens from my Cabi- 

 net in accordance with the classification of Albers, I prepared 

 and annex a copy of a Catalogue of all the species which inha- 

 bit North America (exclusive of the Pacific Coast and Mexico) ; 

 the order in which they are given is based on that of Albers, but 

 with changes in agreement with, and so as further to illustrate 

 the views herein expressed. 



Comparing my Catalogue with the lists of Albers, it will be 

 noticed that I place together at the commencement, H.fuli- 

 ginosa and the allied species. I do so because several at least 

 of the animals of those species are known to have the mucous 

 pore or slit on the posterior termination of the foot, in which 

 they agree with the animal of the genus Zonites. 



Dr. Binney (Terr. Moll. II.), in his descriptions of the animals 

 of the undermentioned species, gives the following among other 

 characters : 



H.fuliginosa Griff. — "a double marginal furrow runs along the sides 

 of the foot, from the head nearly to the posterior extremity, where it 

 passes upwards, and joins that from the opposite side, leaving posteriorly 

 a flattened rounded extremity, somewhat prominent and glandular. 

 Upon the centre of the extremity is a longitudinal fissure, or sinus, 

 which is sometimes expanded, and at other times closed and invisible. 

 Secretion of mucus from the extremity profuse." (p. 223.) 



H. laevigata Raf. (lucubrata jBinn.) — "margin of foot furrowed, fur- 

 rows meeting over posterior termination. Caudal extremity bluish 

 above, with a gland." (p. 225.) 



H. inornata Say. — " a marginal furrow extending along the edges of 

 the foot, and meeting above and before its posterior termination. Behind 

 the junction is a prominent, sub-conical, bluish-white gland, on the extre- 

 mity of the foot." (p. 227.) 



