925 
of Edinburgh, Session 1885 - 86 . 
rationalised. In the history of the pollen grain Strasburger dis- 
tinguishes the vegetative, apparently non-functional, from the gene- 
rative or essential nucleus. On the present view, the latter would 
be regarded as emphatically katabolic, the other half as less so. 
Similarly, the basal portion of the zoospore-fonning cell in certain 
Algae, the unused remnant in the antheridium of Salvinia and other 
forms, the “ Bauchcanalzelle ” separated in the differentiation of 
Conifers and Archegoniates, and other cases noted by Strasburger 
and others, admit of being interpreted as separations of anabolic or 
katabolic portions, as the case may be. That such a separation may 
take place in cell division is illustrated on the present view, for 
instance, in the primitive reproductive cell of a Sagitta , which 
divides into two portions, afterwards developing to form ovary and 
testis respectively. 
(3) In regard to fertilisation, which forms, indeed, the central 
problem of sex, numerous theories have been proposed; some authors, 
e.g., Strasburger, asserting the absence of any essential physiological 
difference ; while, according to others, like De Bary, the difference 
is indeed profound. Sachs suggested the analogy between ferment- 
ation and fertilisation, while Rolph regarded the process in its 
nature and origin as distinctly nutritive. It has been already 
noted, in regard to the origin of fertilisation, that the almost 
mechanical flowing together of exhausted cells is connected by the 
stages of multiple conjugation with the ordinary form of the latter, 
while the respective differentiation of the two elements effects the 
transition to fertilisation proper. Historically, then, fertilisation is 
comparable to mutual digestion, and the reproductive process has 
arisen from a nutritive want. With the differentiation of the ele- 
ments along anabolic and katabolic lines, the nature of the fertilising 
act becomes more definite. The essentially katabolic male cell, 
getting rid of all accessory nutritive material contained in the sperm- 
cap and the like, brings to the ovum a supply of characteristic 
katastates, which stimulate the latter to division. The profound 
chemical differences surmised by some are intelligible as the out- 
come of the predominant anabolism and katabolism in the two 
elements. The union of the two sets of products restores the 
normal balance and rhythm of cellular life. RolplTs suggestion is 
thus included and defined. 
