86 



Univalve Shells. 



sometimes covered with a greenish epidermis. It has six or seven 

 whorls, of which the body whorl is very large, and constitutes half 

 the length of the shell." 



This whole region abounds with fine Helices, for which family the 

 moist woodlands afford suitable habitats. The following catalogue 

 of univalve shells, found on "the Reserve," is from the pen of Dr. 

 K., the whole of which are in his collection : 



* " H. harpa. — I was suspicious from the description and figure of this shell in the 

 2d Vol. of Long's Expedition to the St. Peter's, that Mr. Say had described an imma- 

 ture shell of some large species of Pupa. On examining his specimen, deposited 

 in the Academy of Natural Sciences at Philadelphia, lam convinced that such was 

 the fact. Both the Pupa ovata and arrifera, just before they form the perfect 

 mouth, answer Mr. Say's description and figure above referred to." 



t " Helix glaphyra and inornata of Say, and H. fuliginosa of Griffith, are only 

 different ages of the same shell, if the specimens which I have received from the 

 Philadelphia conchologists be labelled correctly. When the shell is young, the 

 umbilicus is contracted, and the labrum not expanded. It then is called the gla- 

 phyra. At a more advanced age, the labrum expands and forms a large aperture, 

 but the umbilicus still remains unchanged, and at this stage it is iheinornata. An 



