48 PENIKESE. 



ering whatever, and were then called slugs; that these 

 were nocturnal in their habits, and committed exten- 

 sive injury to gardens, which they are fond of inhabit- 

 ing; that slugs do not hibernate, though they become 

 torpid. 



This, however, formed but a small portion of a 

 single lecture: yet is there not here, even, abundance 

 of food for thought and incentive to search still furth- 

 er into the mysteries of Nature? 



Professor Morse is, evidently, an ardent evolution- 

 ist; yet in spite of his natural inclination to protract 

 his lectures into some abstruse features of evolution, 

 or of Darwinianism, there is always much valuable in- 

 formation in them that is carefully noted and remem- 

 bered by every person present. Sometimes he tells 

 us about that most wonderfully curious appendage of 

 the bivalves or lamellibranchs, the crystalline style, 

 and of how it has no attachment to the body, this 

 leads to an investigation, and our discoveries are 

 marvelous. 



One of his talks is devoted to pearls, and we learn 

 that pearls are formed by the retention by the mantle 

 of foreign particles, the irritation of which causes a 

 pouring out of the secretions of its body substances 

 thus pearls grow. But while we are jotting this down, 

 we hear the equally surprising fact that, though with 

 the majority of shells both sexes are combined in the 

 same animal, with the Unios, or fresh-water bivalve 

 shells, the sexes are distinct and comprised in differ- 

 ent individuals; but he failed to tell us how gener- 

 ally, or in what special families, this bisexual arrang- 

 ment exists throughout the molluscous kingdom 

 this, then, would be a capital point for investigation 

 for some enthusiastic naturalist or specialist in this 

 department, for I do not believe that it has e^er been 

 fully or accurately determined. 



At still another time we learn that the shell itself 

 does not obtain its color from the color of the food 

 which the animal eats, as many formerly supposed. 

 Of many samples given, the Professor laid particular 



