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POPULAR SCIENCE REVIEW. 
During the formation of these coats, the direction of the ovule 
usually undergoes a change ; originally subglobose in shape, it 
becomes more and more egg-shaped. At first resting on the 
“placenta” without any intervening support, it ultimately 
becomes raised on a little stalk, “fimiculus,” which gradually 
emerges from the placenta, and bears the ovule upwards with it ; 
in the outset straight and without bend, it gradually, as its 
stalk elongates, becomes more or less curved, so much so, 
sometimes, as to become completely inverted ; the true apex of 
the ovule, which originally pointed towards the upper or distal 
end of the ovary, is now turned towards the opposite extremity. 
While, all these changes have been going on on the surface of 
the ovule, others not less remarkable have been taking place in 
the interior. The nucleus, or primary pimple, which we left as 
a mass of growing cells all about of equal size, now begins to 
show one large cell in the centre, which in some sense might 
be termed a mother cell. This rapidly increases in size so 
as very greatly to exceed the adjacent cells, and in it float 
one or two minute vesicles, which go by the name of the 
germinal vesicles, and one of which is destined to form the 
new plant.. The ovule is now complete as to its organisation. 
There are variations in different plants, but in essence, the 
changes which occur are uniformly such as just described. 
Here, then, is the ovule complete ; it is no seed yet ; it would not 
germinate, using that term in the ordinary acceptation; it may 
become a seed, or it may, for lack of the proper stimulus, grad- 
ually decrease, shrivel, and become obliterated. Speaking 
broadly, it may be said that of hundreds of ovules scores only 
become seeds. In some cases, no doubt, every single ovule 
becomes a seed, but this is the exception rather than the rule. 
How, then, does the ovule become the seed ? In replying to 
this question we can only do so in general terms. The ashes of a 
dead controversy are still warm. It is necessary to tread care- 
fully, nevertheless the way is now pretty clearly marked out, 
and we may walk confidently where, a short time since, fierce 
conflicts were being waged between combatants of nearly equal 
prowess, so that for those anxiously awaiting the issue of the 
controversy, there was but little rest or certainty of belief. 
Dropping all metaphorical allusions, and returning to the history 
of the seed, we now come to the period of its fertilisation ; to 
the time when, in consequence of processes to be presently de- 
scribed, a new plant is formed within the ovule, which now for 
the first time becomes a seed properly so called. 
Space will not allow us even to analyse the records of botany, 
and show by what steps, and by whose assistance, we have arrived 
at our present knowledge of the process of fertilisation. We 
must content ourselves, in general terms, with giving, as clearly 
