LECTURES. 47 



the ground; how they crawl from their places of con- 

 cealment and sun themselves, on warm spring days; 

 that there were no distinctions of sex amongst them 

 both genders being combined within each animal; 

 and that a little after the early spring they begin to 

 lay their eggs, in large numbers, bunched together, 

 and sticking to each other by a mucilaginous sub- 

 stance that also held the bunches to the boards, 

 stones, bark, or leaves under which they were laid; 

 snails' eggs are opaque and white, being longer than 

 broad. 



Then we learned that, if the weather were not too 

 damp, the young animals, with complete, though at 

 first small,shell, appeared in the gelatinous substance 

 surrounding them, in a very few days after the eggs 

 were laid, though it generally took nearly a month 

 for them to become fully hatched; that warm weather 

 hastened the hatching process, though the eggs were 

 seldom if ever laid in the snn; that the young hatched 

 themselves, by eating the shell of the egg which in- 

 closed them; that their growth was a rapid one; and 

 that they fed upon vegetable food. 



Here the Profeesor stopped to describe the teeth 

 and tongue of snails, and to draw innumerable dia- 

 grams of these organs, representative of the different 

 groups, families, and genera of this portion of the 

 molluscous kingdom. In continuing, he said, that 

 there were several species, however, which preferred 

 animal food, one variety even feeding upon the 

 earth worms while another eat its own eggs. At 

 about the first frost snails hibernate, or in some snug 

 retreat, like that in which it has lived during the 

 summer, goes into regular "winter quarters;" it retires 

 further and further within its shell, forming mucous 

 membrane after mucous membrane as it goes, until 

 there are five to eight or more perhaps; the functions 

 of the body move slower and slower, until they at 

 length wholly cease; and that American species, as a 

 rule, are less gregarious than those of other regions. 

 Some species, he said, had no shell or other hard cov- 



