CONTRIBUTIONS TO BOTANY. 
165 
Styrax, Strigilia, Cyrta, Parnphilia, and Foveolaria does not 
exist in Halesia and Pterostyrax, this fact is of little importance 
in an ordinal point of view, in the presence of other more essen- 
tial characters ; for in some unquestionable natural orders, the 
Melaatoinacea for instance, the calyx, though usually adnate, is 
very often free. But this admission does not destroy the distinc- 
tive character of the Symplocacea, in having a nearly inferior 
plurilocular ovary, that is to say, its being enclosed within an 
adnate calyx from the earliest stage of its development up to 
the period of the ripening of the fruit. In Pterostyrax, on the 
authority of Zuccarini, the ovary is acknowledged to be half 
superior, as I have found it in Halesia, in which genus its su- 
perior moiety is free, rising above the staminiferous disk in a 
conical form ; the calyx is at first so loosely adherent to the 
lower part of the ovary, that it is easily separable from it by the 
introduction of a blunt point. In Styrax and Strigilia, how- 
ever, the ovary is wholly superior, although I have observed in 
Styrax officinale and in Strigilia ovata that the base of the ovary 
is very slightly imbedded in the torus at an eaidy stage, while 
m other cases it is generally free ; but even in these two in- 
stances, in a short time, by the upward growth of the ovary, 
this minute portion emerges, and the fruit is quite free from the 
calyx. In Styrax and Strigilia, the greatest increment of the 
ovary occurs in its upper portion, and the persistent calyx in- 
creases very little in size ; but in Halesia there is no growth 
whatever of the upper portion, which remains unchanged, per- 
sistent, and crowning the fruit, the whole amount of increment 
being confined to the lower moiety, and with it a corresponding 
growth of the tube of the adnate calyx, as I will presently 
show. 
2. Since I have been able to examine Halesia and Pterostyrax, 
1 am satisfied that in these cases the aestivation of the corolla is 
decidedly imbricated, as shown by Dr. Gray ; but it is certainly 
valvate, as I stated, in every other instance I had met with, 
especially in Strigilia, Parnphilia, and Cyrta. However import- 
ant this feature of aestivation may be in some cases, as an acces- 
sory character, it is not considered of any ordinal importance in 
many families ; in proof of which I need only refer to Rubiacea 
as furnishing numerous examples of both kinds. 
3k. Although it be quite true, in a general sense, as I affirmed, 
that the stamens are uniserial in Styracece, and pluriserial in 
Symplocacece, I admit that they are uniserial in Burberina, and 
that in Halesia the stamens are often four times the number of 
the petals ; but in the latter case the filaments, though more 
numerous than usual, still only constitute a single whorl, being 
slenderly agglutinated by their adhesion to the base of the co- 
