200 



H. sericea. Mr. Lowe has noticed it as inhabiting 

 Madeira. In all probability it derives its origin from 

 a preglacial epoch. 



This little snail does some mischief in our gardens by 

 nibbling before the dawn of day the leaves of some of 

 the more succulent plants. The Rev. Revett Sheppard 

 remarked that it was an amphibious species, being "fre- 

 quently found some feet below the surface of water on 

 stakes and piles, upon which it ascends and descends at 

 pleasure ; " and he added that the eggs resemble those 

 of birds and retain their form without shrinking. Ac- 

 cording to M. Bouchard-Chantereaux,the H. hispida lays, 

 between the months of April and September, 40 eggs, 

 which are globular, white and opaque ; the fry are born 

 at the end of the twentieth to the twenty-fifth day, and 

 emerge from the egg with nearly one whorl of their shell 

 formed ; and more than half of this embryonic shell is 

 then covered with minute red and straight hairs of a 

 tolerably strong consistence. The summit of the spire 

 is quite smooth and polished. The black spots on the 

 mantle are sometimes visible through the semitrans- 

 parent shell, even in dried specimens. The first-formed 

 whorls are often whitish, in consequence of their not 

 being occupied by the animal 



The H. plebeia of Draparnaud seems to be one of the 

 numerous varieties of this species, judging from his 

 description and a comparison of specimens thus named 

 which I received from his friend M. D'Orbigny at 

 Rochelle. According to Moquin-Tandon, the umbilicus 

 of this variety is very narrow. Several other species 

 have been carved out of this variable and ubiquitous 

 form by Continental conchologists. 



