102 ON THE SEXUAL ORGANS OF THE CYCADACES. 
When we examine the relations of the sexual organs in plants, it 
seems in many cases that the function of fertilization has been rendered 
in some manner difficult or even impossible. It might be said that 
nature does not wish to see its end attained except circuitously ; as far 
as Angiosperms are concerned, a more precise knowledge of insect- 
agency has already to a considerable extent penetrated the mystery. 
But there are other great divisions of the vegetable kingdom in 
which this agency has no place, and it is these which were already in 
existence before haustellate insects. I regard as such all the Crypto- 
gams; among these the spermatozoids move towards the female 
organ by means of humid surfaces, drops of water, etc. Among the 
diccious and moneecious Phanerogams which have preceded herma- 
phrodite species on the surface of the globe, their pollen is carried 
in excessive abundance by the winds, and the chances are greatly in 
favour of one of the millions of grains arriving at its destination. 
As to Cycads, I do not at present know any property which would 
be of a nature to attract insects in particular towards their female 
cones, either from nectar in the flowers, colour, or odour; at the same 
time, when one takes into consideration their being dicecious, and the 
complete occlusion of their female cones (except in the Cycads, where 
the ovules have the exostome outside, which would allow access to the 
pollen-grain), it becomes almost impossible to comprehend how the 
for example, our most conspicuous species or trees hold, for the most part, a 
lower position than a large proportion of our herbaceous plants, whose perish- 
d leave no trace in deposit i ight, ho 
cena and osi of Finden in eben ance. Without a knowledge to the 
rary, these might lead an observ: ipie. such a deposit to the con- 
eranc that the Depulifore. almost pibe ea posed our jM iens Even 
without this consideration, it will hardly be er kied that Angiosperms had at 
tan : 
Rie connection between the periods of appearance pd — of Angiosperms 
h llate i is undou pea interesting. It , however, be re- 
sidinbers d that it rests on negativ tispa which in den and is necessarily far 
from conclusive. Their i in unii y be the cause of our finding them 
associated in time, iex = igi — id; d is one of them may have preceded 
the other, without our h ing at present evidence of the fact. Theories as to 
evolu vi sho ould | only e sparingly ilh illustrated Ares geo Ades phenomena, and 
mple, Dr. Debey has obice 
about «d species of “insects from hn Aic Chapt beds. Yet these 
pi to y uc Curculionide or Carabide, which are mandibulate insects. 
