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the Cucurbitaceae in particular. He declares that Amici had 
taken the inner integument for the nucellus and the nucellus 
for the embryo-sac. Schleiden contends that the embryo-sac 
is present before the opening of the flower, that there is no 
canal in the apex of the nucellus, and states that he, him- 
self, has traced the pollen-tube in its course in Pepo, Melo, 
Cucumis, Lagenaria and Momordica, and especially in 
Momordica has seen the male generative nuclei emerge from 
the pollen-tube. 
In the following year Facchini™ came to the defense of 
Amici, stating the nine propositions which that author pub- 
lished, along with his plates. The effort, however, to vindi- 
cate Amici was not very successful. 
In the same year (1845) Schleiden” returned to the attack 
and gave us the first account of the embryo-sac before ferti- 
lization in any of the Cucurbitaceae. In Cucurbzta Pepo he 
figures an ovule with its parts correctly differentiated and 
states that the small embryo-sac is present before the opening 
of the flower, and that it has only slightly enlarged at the 
time of the entrance of the pollen-tube. He says further: 
‘It is easy to observe the pollen-tube in its course from the 
stigma through the conducting tissue. At the time when the 
flower wilts and falls off, the tubes have reached the ovules, in 
some cases at least. The ovary at this time is about 21 mm. 
long and 18 mm. in diameter. When the ovary has become 
35 mm. long and 22 mm. in diameter the ovule is 4 mm. 
long, 2 mm. broad and 1 mm. thick. When the pollen-tube 
has reached the apex of the nucellus the latter has partly 
broken down: the pollen-tube quickly runs through its 
length, bulges out in it and fills it with a starchy substance 
so that it is quite dense. The pollen-tube and the embryo- 
sac seem to be fused together.” The tip of the nucellus, he 
further states, becomes disorganized as the pollen-tube ex- 
pands in it, and immediately afterwards the extension of the 
embryo-sac toward the chalaza begins. When the ovary has 
reached the length of fifty millimeters the odspore becomes 
visibly cellular in structure. 
