94 Mr. Brown’s Observations on the 
that it is more analogous to the outer calyx of Scabiosa; which 
M. Cassini seems to consider sise in its nature ir -— 
these parts. = | | 
But the order of expansion in. re vw is, c — 
some degree of irregularity; from centre to: circumference, or 
that of the compound capitulum, seems to decide the question 
respecting the envelope of each flower, and to establish its iden- 
tity with involucrum : -nor does this involucrum differ materially 
from that of Echinops, except in the red uced: number and son- 
fluence of its component parts. - | 
The real structure of Casulia is rares less obvious. 
This genus, which was first published" by Dr. Roxburgh *, is 
referred by him to Polygamia segregata; the tubular envelope or 
involucrum nes un esc ninm as comam from the in- 
. cluded ovarium. 19 j i 
Koenig, on the sium hand, by imp: the: genus was discovertd, 
and whose account of it is given in the same work, describes the 
partial involucrum of Roxburgh as the surface of the ovarium 
itself; its segments being, according to him, a pappus of two 
leaves. And lastly Willdenow, regarding this involucrum as merely 
paleæ of the receptacle, refers the genus to Polygamia æqualis ; 
in which order itis continued, both in Persoon's Synopsis, — 
the second edition of Mr. Aiton's Hortus Kewensis. - 
This last view of the structure seems the most erroneous of any, 
and was probably adopted by Willdenow, in consequence of his 
having added to the genus a second specics not really belonging 
to it, and which I shall have occasion to notice in another part 
of my subject. 
An examination of the parts of fractiientipte in different stages 
* In Coram. Plants, i. p. 64. t. 93. : 
reconciles 
