28 Mr.,Brown, on the Proteacee of Jussieu. 
velope, it will be still better to call it perianthium or perigoniam, 
_ which latter term was proposed by Ehrhart, and is adopted by 
Decandolle. | | 
A circumstance meriting the attention of the theoretical bota- 
nist, respecting the calyx in this order, is its invariable division 
into four leaves or segments ; for the single exception noted by 
Linnzus in his description of the male flowers of Brabejum, he 
himself seems afterwards to have distrusted, from the manner in 
which.he has introduced it into the amended generic character 
given in the Mantissa; and I may add, that in nearly 400 species 
of the order, which I have examined, I have not met with a 
single exception to this rule. ' 
. With this. uncommon constancy in point of number, it is re- 
markable that there is, in the whole order, a strong tendency to 
irregularity in form, the various kinds of which are. of. great im- 
portance in characterizing genera. barm an | b 
- Before the expansion of the calyx.the margins of its segments 
are applied to each other; and from the unequal degrees of co- 
hesion in many cases subsisting among them after expansion, se- 
veral kinds of irregularity arise. I am not sure that any term 
has been contrived for this manner of estivation, except it be 
the @stivatio valvata of Linn:us ; but as he has not defined it, and. 
as his commentator Reuss has given the very different »stivation 
of grasses as an example, I have, in introducing this circumstance 
into the general description of the order, specified it at length. - 
From the colour of the calyx, many genera of Proteacex are 
indicated with tolerable certainty. Thus Synaphea is distinguished 
from Conospermum by its yellow. flowers; and no instance of 
yellow flowers has been met with in the numerous genera Serruria 
and Spatalla, nor any of purple in Leucadendron. In some ge- 
dre nera 
