AMPULLARIA DEPRESSA. 7 



The eggs are soft when first excluded, but ac- 

 quire the hard shell within 12 hours, from the 

 action of the atmosphere. As the egg passes 

 out of the ovarium, it appears to be impelled 

 on a sheet of mucus until it reaches the point 

 to which it is to be attached, when it is accu- 

 rately adjusted by the mere direction of the 

 fluid, the animal remaining inactive. As soon 

 as the first egg has been secured to its place, 

 another is excluded from the ovarium and slowly 

 descends in the mucus to its place." Couper, 

 in letters. 



OBSERVATIONS. 



Say changed his first trivial name because he 

 supposed it to be preoccupied for a fossil spe- 

 cies, but as this proves to be a Natica, the first 

 name need not be relinquished.* 



Mr. Lea alludes to Say's species and remarks 



* M. Deshayes (Lam. viii. 551) thinks this species 

 (Lam. No. 7) and the succeeding ones in the same work, 

 belong to Natica. I would extend the observation to some 

 of the preceding fossil species, as A. spirata, A. acuminata, 

 and A. acuta. 



