SECT. I. APPENDAGES OF THE FLOWERi 1?5 



of the umbel are not invested by the involucre like 

 the flowers of plants, having confessedly a common 

 calyx ; and because they are besides individually 

 furnished with a proper calyx more or less con- 

 spicuous, which renders the existence of a common 

 calyx at least dubious, unless it is obviously sanc- 

 tioned by the evidence of analogy, as in the genera 

 Dipsacus and Scabiosa. 



The involucre is therefore merely a leaf-like ap- 

 pendage of the fructification, and no part of the 

 flower ; being regarded as such by Linnaeus only 

 because, with Artedi, he believed it impracticable 

 to characterize the different genera of the Umbelli- 

 fcr& without its aid, and was consequently com- 

 pelled to regard the involucre as a calyx, and the 

 spokes of the umbel as divisions of a branched re- 

 ceptacle, in order that he might apparently not 

 transgress his own fundamental and golden rule of 

 deducing the generic character exclusively from the 

 parts of the flower and fruit ; which rule he trans- 

 gressed in fact without any absolute necessity, the 

 flower and fruit of the Umbdlifcra being found suf- 

 ficently adequate to the purpose of generic discrimi- 

 nation, as well as the flower and fruit of other tribes 

 of plants.* 



As Linnaeus elevated the involucre of the Umbetti- 



fera to the rank of a common calyx, so M. Mirbel 



reduces the common calyx of compound flowers to 



the rank of an involucre.-}- But in the latter case 



* Smith's lulrod. p. 3U. t Anat, Veg. tome ii. p. 202, 



