natural Family of Plants called Composite. 137 
points to this extremity cannot in strict propriety be described as 
directed towards the umbilicus. M. Cassini has not noticed the 
direction of the radicle; either from supposing it constantly con- 
nected with that of the ovulum, or, which is more probable, from 
not having ascertained it. 
_ These distinctive characters may be considered as fully sufficient 
to authorize the separation of Boopidee from Composite ; yet the 
same differences exist between certain genera referred and really 
belonging to Rubiacee and the principal part of that order. 
. There are, however, three other characters unnoticed by M.Cas- 
sini, which distinguish the flowers of Boopideæ from the herma- 
phrodite flowers of the whole of Composite; namel y, the accretion 
of the base of the style with the tube of the corolla; the absence of 
the epigynous disk or nectarium ; and the longitudinal subdivision 
of each cell of the anthera by a “receptaculum pollinis,” as in most 
- . other families,and of which, indeed, there seems to be the rudiment 
in the syngenesious genus Petrobium, described in the preceding 
paper. 
In the partial cohesion of the anthere, in which they resemble 
Jasione, they certainly differ from all known Composite: but as 
in certain Composite the anthere are very slightly connected or 
entirely distinct ;—this, though a remarkable circumstance, can 
hardly be employed as a distinguishing character. 
‘The principal characters in which Boopideæ differ from the 
greater part, though not from the whole of Compositæ, are the 
corolla being continuous, or not jointed, with the ovarium ; the 
antheræ having no membranaceous appendix at top; and the un- — 
divided stigma. : 
Boopide« differ from Dipsaceæ in the vascular structure and val- 
vular estivation of corolla; in the estivation, insertion, and con- 
VOL. xtti. T nexion 
