1884.] 
male flowers only appear ; but if light be in excess, female flow- 
ers alone will be produced ” (Carpenter, Comp. Physiol., 1851, p. 
979). According to Sachs’ account of the conditions on which» 
cell-growth and cell-division respectively depend, these results 
_ obtained by Knight agree with the theory of sex here proposed. 
“In the case of the buds of the higher plants their reservoirs 
of reserve material are the bulbs, tubers, rhizomes, parts of the 
stem, cotyledons and endosperm; after the complete exhaustion 
_ Of these, growth ceases in the dark but continues in the 
_ light, because the assimilating organs can then produce new 
_ ‘material. This relation of growth, which is connected with cell- 
i division, to assimilation, is especially clear in algæ of simple 
_ Structure, which assimilate in the day-time under the influence of 
light, while cell-division proceeds exclusively, or at least chiefly, 
atnight. The swarmspores are also formed at night, but swarm 
only with the access of daylight. In some Fungi, also, the split- 
_ tng up of the protoplasm in the sporangium into a number of 
‘pores takes place only in the night, the -spores being thrown out 
: 
The Theory of Sex and Sexual Genesis. 787 
"a the access of light. While, therefore, in the larger and more 
highly organized plants assimilation and the construction of new 
- tells out of the assimilated substances is carried on in different 
_ Parts but at the same time, in small transparent plants, in which 
_ iS Parts where these functions are effected are not surrounded 
oh Opaque envelopes, they take place at different times ” (Botany, 
_ 753). The conditions on which cell-division depends are no 
_ _ ` Present both in light and darkness, but in the light there 
_*4 predominance of the conditions of growth. 
Speaking of the segmentation of the animal ovum, Stricker 
= “In the fecundated egg the spermatozoa must be regarded 
- he agents from which the first excitation proceeds. There 
fan be no doubt, also, that in the act of fission a high tempera- 
“uc Plays an important part” (Manual of Histol., p. 46). This 
ee words with the interpretation of the results of Knight's 
“periments required by the theory of sex here proposed. 
ae is evidence of a similar kind to that now given with 
tatt to plants, showing that in animals likewise the sex may 
_ “mined or controlled to a greater or less extent by condi- 
of nutrition, « According to Girou, female domestic anı- 
e~“ more females when well nourished and left in repose 
“8 much worked and on spare diet ” (Allen Thomson, 
*YI1.—no, VII, 
le aa Eg a a Fat a a Nok a TLE Salt get a R a nm aL 
50 
