1898] ‘NUCLEAR REDUCTION’ LLY 
generation from which, after it had attained sexual differentiation, 
offspring was developed having a double number of chromosomes. . . 
it is the re-appearance of the primitive number of chromo- 
somes as it existed in the nuclei of the generation in which 
sexual differentiation [rather eell-fusion, for whether it be 
sexual or isogamous makes no difference to the point] first took 
place.” If we are to take literally the phrases that I have spaced, 
we shall have to assume that two such plants as the onion and 
the turban-lily have independently developed a pairing process; for 
the number of the nuclear segments is 8 and 16 in the former, 12 
and 24 in the latter; the same would apply to the two forms of the 
roundworm of the horse, with 2 (4) and 1 (2) segments respec- 
tively—which is absurd. Yet so much of the essay is taken up in 
proving that asexual reproduction is the older mode, not only in 
primitive organisms, but in individual Orders of higher organisms 
that one wonders if Strasburger has not really missed the incon- 
ceivability of his statement as it stands; and hence I cannot accord 
to the explanation above-given the full weight of his distinguished 
authority, as I should wish to do. | 
Now we have seen that the process of ‘nuclear reduction, despite 
its name, involves no necessary reduction in the quantity of nuclear 
matter, but only in the number of the segments into which it is 
distributed. Hence the process cannot have the physiological 
function ascribed to it as a ‘preparation for gamogenesis’; and, 
since we have noted its occurrence at the inception of a long 
series of cell-multiplications, this physiological function would be 
absolutely useless. 
II 
A word about the functions of the chromatin or nuclein in 
nuclear division. The amount of chromatin in a nucleus is 
constantly changing; very often after a cell is formed the nuclein 
is much reduced in amount, and with this reduced amount the 
cell does all its individual life-work. At the approach, how- 
ever, of cell-division, the nuclein grows, and reaches a maximum 
at the commencement of the nuclear division that precedes that 
of the cell as a whole; the nucleus of the daughter-cell repeats 
the conduct of its parent. Whatever be the function of the 
chromatin in the ‘working’ cell, as we may term it, it is 
evidently less important than its function in the dividing 
cell. The achromatic substance of the nucleus (linin) forms 
the basis, as it were, of the nuclear segments, the strands on 
which the chromatin is imbedded in the form of granules, like 
the string of a necklace, or better, the braid in beaded passe- 
menterie; these granules first split, and then the threads on which 
