Notes on certain Terrestrial Mollusca. 155 



XIX. — Notes on certain Terrestrial Mollusca, with Descrip- 

 tions of New Species. 



By Thomas Bland. 



Eead September 25, 1365. 



In a note accompanying my description of Proserpina 

 Swifti from Venezuela {Ann. viii. 13, 1863), I gave the cha- 

 racters of the Family Proserpinacea from Gray's " Guide to 

 the Mollusca" and of the Genera Ceres and Proserpina ; indi- 

 cating also the number of parietal and palatal laminae in each 

 of the species. I added the following remarks : 



" It will be noticed that the existence of one or more parietal or pala- 

 tal teeth, iu addition to the fold or tooth on the columella, is given as a 

 characteristic of the Family. 



" The recent discovery, however, of the species described in this paper 

 as P, Swifti, having the columella! fold only, shows that it alone, so far 

 as the teeth are concerned, is a constant character. 



"P. Swifti does not properly belong to Proserpina as defined by 

 authors ; but as that genus embraces species with and without palatal 

 teeth, it may fairly be enlarged so as to include those with and without 

 parietal teeth, all having the columellar fold characteristic of the family." 



On a late examination of some terrestrial shells collected by 

 Dr. Berendt in Mexico, I was surprised to find a species with a 

 slightly elevated parietal lamina, but no columel- 

 lar fold, and yet having externally the appear- 

 ance of a Proserpina. On opening several exam-* 

 pies, I discovered that the septa of the whorls were 

 destroyed, as in the Family Proserpinacea, to which 

 I concluded that it belongs. 



P. Swifti, of which figures are annexed, afforded 

 proof that the parietal and palatal laminae can no 

 longer be regarded as Family characters, and it is now shown 

 that the columellar fold is not constant. 



NOVEMBER, 1865. 12 Ann. Lto. Nat. Hist., Vol. VIII- 



