a Nalional Museum, 313 



SHELLS. 

 The shells of the third order of vermes are so various and 

 so beautiful as to deserve a distinct place in the Exhibition, 

 They are commonly arranged in three Orders : 1. MuLli- 

 valves. IL Bivalves. IIL Univalves,— S&z Paley, 306, 307. 

 Thirty-six Genera. 



PLANTS. ■ 



Pictures and dried specimens displaying the characte- 

 ristics and interesting peculiarities of classes, orders, ge- 

 nera, &c. 



We discover in plants, as well as in animals, numerous 

 relations to the preservation of individuals, and of species ; 

 but we perceive also a limitation of the faculty of motion, 

 which renders it doubtful whether any of their movements 

 are spontaneous, or can be considered as proceeding Irom 

 internal power, independent of the immediate agency of 

 some external force attractive, repulsive, or impulsive. 



Their forms, like those of animals, are composed of he- 

 terogeneous particles, which, when once separated, display 

 no tendency to remiite in similar form. They are composed 

 in great measure of numerous tubes, which convey juices 

 to each part necessary to nutrition and to growth. The 

 period of vegetable like that of animal form is limited; — 

 of various extent in different species. Like animals, plants 

 grow to a limited magnitude according to their species, and, 

 having attained to a certain growth, soon tend to decay.— 

 Moderate heat and light are requisite to their sustenance or 

 "Vvcll-being. They are subject to variations of health, from 

 defect or excess of nutriment. The organization of some is 

 adapted to subsistence in water. VVatry situations are de- 

 structive to others. Relations exist between different parts 

 of vegetable forms, and between diflerent individuals, oji 

 which depends liie continuance of their species. Plants are 

 incapable of locomotion ; but provisions are ordained for 

 the conveyance of their seeds to proper distances, that they 

 may have room for growth. Analogies of plants to ani- 

 mals may be specified to a great extent ; and in the com- 

 6 plttion 



