172 DEVELOPMENT OF THE OVULUM 
the nature of the attachment of the ovulum of this plant, a 
transverse section near the base will shew the coats on one 
side only. Two certainly exist, but both appear shortly 
after fecundation to become adherent to the cavity of the 
ovary. - 
M. Mirbel soma appear to coincide with Brongniart 
regarding the nucleary albumen of Zea, although his 
remarks are confined to the coats; but he very properly 
observes in opposition to M. Brongniart's ideas of his sin- 
gle tegument being tegmen, that many primines of other 
families than grasses, have no apparent vessels, pp. 49, 50. 
Subsequently at page 55, he adopts Brongniart's views. 
. Brongniart's view of Mays is this, and it is probable 
that the difference arises from his having observed the ovu- 
lum after fecundation. The ovule, according to him con- 
sists of a thick outer coat, which he supposes to be tegmen, 
and a conical body, which he terms nucleus. The most curi- 
ous part of the statement is the existence of an opening in 
the tegmen (my nucleus), in which the apex of the nucleus 
is engaged. "The existence of the two coats before fecun- 
dation at once sets this question at rest. Even if my ob- 
servations be found erroneous, subsequent experience has 
proved, that the fleshy mass may be nucleus. To this it has 
every affinity, as has the sac to the embryonary sac. He 
subsequently describes Graminez much more rightly, enfin 
ans certaines plantes, presque toute l'amande est formée 
par un parenchyme homogéne, et le sac embryon ainsi ne 
s'offre que comme une petite cavité ap Sin du mamelon 
d'impregnation p. 107. 
The albumen has been shewn is M. Raspail to consist of 
masses of starch, each of which is surrounded by a mem- 
branous utricle. This formation is easily seen. Mr. Brown 
may perhaps be supposed to allude to it, as he speaks of 
it as a deposition for the secretion of granular matters within 
the cells of the nucleus, or utricle of the amnios. 
For the first precise information as to the formation of 
this organ, we are indebted to Mr. Brown. He distinctly 
points out that the albumen is formed in most instances 
