CHAP. II. 
OVULE. 
217 
Besides the two external integuments, Mirbel has remarked 
the occasional presence of three others peculiar to the nucleus, 
which he calls the tercine^ quartine, and quintine. 
The former is the external coat of the nucleus, and is very 
generally, if not universally, present. As I am unacquainted 
with the distinctions between these supposed integuments, 
especially the quartine, I can add nothing to the following 
remarks of Mirbel upon the subject : — “ The quartine and 
quintine are productions slower to show themselves than the 
preceding. The quartine is not very rare, although no one 
has previously indicated it ; as to the quintine, which is the 
vesicula amnios of Malpighi, the additional membrane of Brown, 
and the sac of the embryo of Adolphe Brongniart, I am 
far from thinking that it only exists in a small number of 
species, as Brown seems to suppose. If no one has noticed 
the quartine, it is, no doubt, because it has been confounded 
with the tercine; nevertheless these two envelopes differ 
essentially in their origin and mode of growth. I have only 
discovered the quartine in ovules of which the tercine is 
incorporated at an early period with the secundine ; and I 
think that it is only in such cases that it exists. At its first 
appearance it forms a cellular plate, which lines all the 
internal surface of the wall of the cavity of the ovule ; at a 
later period it separates from the wall, and only adheres to 
the summit of the cavity : at this period it is a sac, or rather 
a perfectly close vesicle. Sometimes it rests finally in this 
state, as in Statice ; in other cases it fills with cellular tissue, 
and become a pulpy mass ; under this aspect it is seen in 
Tulipa Gesneriana. All this is the reverse of what takes place 
in the tercine ; for this third envelope always begins by being 
a mass of cellular tissue, (and at that time it has the name, as 
we have seen, of nucleus,) and generally finishes by becoming 
a vesicle. 
“ I have remarked the fifth envelope, or quintine, in many 
species : its general characters are such as to prevent its being 
mistaken. Its complete developement takes place only in a 
nucleus which remains full of cellular tissue, or in a quartine 
that has filled with the same. At the centre of the tissue is 
organised, as in a womb, the first rudiment of the quintine ; 
