DEGENERATE SEXUAL REPRODUCTION. 1 83 



plasma within the germinal vesicle is an unverirtable myth. That the first 

 polar body is an extrusion of one kind of nuclear substance, and the second 

 something quite different, is another unproved hypothesis. Were the extru- 

 sions markedly different, one might believe it, but they are the same. 

 When a large cell divides very unequally, as in polar body formation, there 

 is some warrant for supposing that the little bud is different from the large 

 cell ; but that two successive divisions, entirely similar in character, are 

 conspicuously different, requires faith. It is allowed by all that each polar 

 division lessens the mass (not the number) of the chromatin elements in 

 the nucleus by a half, but so far as nucleus is concerned there is nothing 

 whatever to show that the first division is qualitatively different from the 

 second. The first may have more cell-substance extruded along with it, 

 and the second may be rather a nuclear than a cell-division, but as regards 

 "plasma" the two are, so far as the facts go, absolutely alike. The 

 second division also follows on the heels of the first without the inter- 

 vention of the usual resting stage. Nor of course is there any proof that 

 a parthenogenetic ovum does not part with half its " germ-plasma" in the 

 first division. The distinction between the two kinds of nuclear plasma 

 is, in plain words, a myth. 



(3.) Weismann's pre-occupation with questions of inheritance has given 

 a bias to his theory, making it morphological rather than physiological. 

 A given quantum of germ-plasma, he says, fits the ovum to develop. The 

 parthenogenetic ovum has this and keeps it. The ordinary ovum has it 

 too, but extrudes it, to get it back again from another source. If this is 

 all the sperm does, one cannot help wondering that such a circuitous pro- 

 cess could ever arise. The entrance of the sperm must be looked at in 

 two ways, — (a) It bears with it certain hereditary characteristics, doubtless 

 in the nucleus for the most part ; (/') it brings with it a stimulus to division 

 of a qualitative character, doubtless in some part in its small cell- 

 substance. This last function — the dynamic function— Weismann wholly 

 denies. The sperm has to him only a quantitative function. Yet in spite 

 of this virtual denial of sex, — i.e.^ of any deep difference between male 

 and female whether elements or organisms, — he does admit a qualitative 

 action after all, for it is out of the mingling of the male and female germ- 

 plasma that all variations arise. 



(4.) Boveri makes an interesting note in regard to Weismann's discovery 

 and theory. There is a tendency, illustrated in ascarids, for the second 

 polar division to limit itself to the chromatin elements, to be a nuclear 

 division rather than a genuine cell-budding. Such a second division may 

 possibly occur in the parthenogenetic ova, while there may be in reality 

 one extrusion. A second nucleus may be formed, and retained, and act 

 the part of a spermatozoon, very much as Minot's theory supposes. 



{g) Our theory of parthenogenesis is not so subtle as 

 Weismann's nor so simple as Minot's. Just as the spores 

 which illustrate the beginnings of sex may sometimes dispense 

 with conjugation and germinate independently, so may ova 

 develop parthenogenetically. These are to be regarded as 

 incompletely differentiated female cells, which retain a measure 

 of katabolic (relatively male) products, and thus do not need 

 fertilisation. Such a successful balance between anabolism and 



