natural Family of Plants called Composilce. 105 



But if these four plants, so extremely different from each other 

 in pappus and form of the pericarpium, really belong to the same 

 genus, as their habit seems strongly to indicate, there can be no 

 reason to separate from them Alcina of Cavanilies, erroneously 

 considered by Willdenow us a species of IVedelia : and Di/sodiuin 

 of Riciiard, published in Persoon's Synopsis, though differing 

 from all the others in the form of its pericarpium and in that 

 of its receptacle, must also be reduced to this genus. If, how- 

 ever, the part described by Linneus as pappus in Melampodium 

 americanum be really such, and if the pericarpium itself vary so 

 widely both in form and surface, it would be inconsistent with 

 the principles of division generally adopted in Composita3, to 

 unite all these plants into one genus, notwithstanding their great 

 resemblance in habit as well as in the other parts of fructifica- 

 tion ; and it would be at least in vain to look for any combining 

 character in this part of their structure. 



A careful examination of the female flowers, especially in an 

 early stage, removes this difficulty, by proving that the supposed 

 external coat of the ovarium, with its various inequalities of sur- 

 face, some of which have been described as pappus, is in reality 

 an involute bractea or foliolum of the involucrum, like that of 

 Micropus, completely inclosing the ovarium, but from which in 

 several species of the genus it is entirely, and in others in great 

 jiart, distinct. 



Craspedia 



first appears in Forster's Prodromus Florulae Insularum Austra- 

 lium, where an essential generic character is given, but no de- 

 scription of the species. The genus is adopted and the cha- 

 racter received without remark by Willdenow in his edition of 

 Species Plantarum, and by Persoon in his Synopsis, Among 

 George Forster's drawings of subjects of natural history made in 

 VOL. XII. p Cook's 



