xxii PREFACE. 
tissue will perhaps by close observation be ascer- 
tained. This fluid abounds in active molecules, 
Conifere.—Mr. Brown is certainly correct in stating 
Gnetum to have naked ovula : but here I think excepting 
its punctuations, the resemblance or affinity ceases, 
the nucleus hasas I have shewn three coatings, but only 
at a certain period of its development, The use 
of this additional coat, the apperance of which is 
sudden, is evidently to ensure fecundation, still 
from the comparative rarity of development of the 
embryo this process is evidently but seldom or at 
least only under particular cireumstances perfected. 
Butomee.—Butomus pygmeus occurs abundantly 
in India from plains up toa height 2000ft. at least 
on the Khasiya hills. — 
Stomata exist on both sides of the leaf, the ovulum 
is anatropous, but the mature seeds closely resemble 
campulitropous. "The embryonary sac although highly 
developed and apparently membranous presents traces 
of cellularity. 
Burmannie,—Several Species areso to say, aphyl. 
lous and such are very probably parasitical. From 
some observations on the structure of the seeds, I am 
led to conclude that the nucleus consist of several 
grumous masses, enclosed within a proper membrane 
I have not been able to ascertain the existence of 
any determinate form of embryo. 
Orchidez.—The filaments are adnate to the style. 
With regards to the mode in which impregnation 
is stated to take place, I hope that certain distingui 
HARTE net air tiene which certainly are, —— 
