170 DESCRIPTION OF THE MUSEUM. 



wish only to obtain a general idea of vege table 

 physiology and the affinities of plants, may behold 

 each species surrounded by those which it most 

 nearly resembles ; and, with a few intervals, may 

 pass by regular gradations from the lilacece to 

 the coniferce, from the tulip and the hyacinth to 

 the fir-tree and the cedar of Lebanon. They will 

 notice some families, such as the lilies, the labiated 

 and the cruciform plants, so natural that a person 

 the least accustomed to observation is struck by 

 the analogy ; others united by less sensible affini- 

 ties, as the rhamoriidece , the euphorbiacece, etc. ; 

 some extremely numerous, as the compound and 

 papilionaceous plants, and others which are li- 



, mited to a few species, as the aristolochice and the 

 hypericece ; some whose characters run into each 

 other, as the cruciferce and the capparidece ; 

 others again abruptly separated, as the umbelli- 



ferce, the rannunculacece , the euphorbiacece , and 

 the cucurbitacece : in fine, they will observe some 

 genera so peculiar, that their place has been de- 

 termined only by systematic considerations, such 

 as the reseda, the nasturtium tropceolum, and the 

 parnassia ; and others whose species cannot be 

 distinguished when found alone, but which it is 

 nevertheless important to separate, as the sixty 

 species of aster, which vary by almost insen- 

 sible shades, but bloom at different periods; 



