gOO 4. Fortpflanzungslehre. 



Reproduction. 706 S. 154 Abbildungen. London, Longmans & Co. 



1910. 



This book gives a very complete account of the phenomena connected 

 with reproduction of the Mammalia, and deals less fully with similar pro- 

 cesses in the lower vertebrates and invertebrates. After dealing with the breed- 

 ing season in different groups of animals and the causes which induce or 

 hinder it, which are both internal and externa], the author discusses the oes- 

 trous cycle and compares it with the human menstrual cycle. The changes 

 in the uterus during the cycle are next fully described; then the processes of 

 oogenesis, Ovulation, and formation of corpora lutea. It is concluded that the 

 mentrual cycle in Man corresponds with the oestrous cycle in the lower Mam- 

 mals, menstruation being comparable with 'prooestrum', and that both are due 

 to changes in the uterus in preparation for the reception of the fertilised 

 ovum. Spermatogenesis in the Mammalia, Insemination, fertilisation, the pos- 

 sibility of the existence of telegony and of selective fertilisation are next con- 

 sidered, and 'artificial parthenogenesis' is shortly discussed. The accessory 

 reproductive organs of the male and their function and nervous mecbanism 

 are fully described, and a chapter on the biochemistry of the sexual organs is 

 contributed by W. Cramer. An especially valuable chapter is that dealing 

 with the testis and ovary as organs of internal secretion, in which the rela- 

 tion between the activity of the festes and ovary and the secondary sexual 

 characters is explained. In the case of the ovary the secretion is produced by 

 the cells of the follicular epithelium or by the interstitial cells, or both, and 

 its increase at certain times brings about the phenomena of prooestrum. After 

 Ovulation tbe secretory cells show still greater activity, becoming converted 

 into the luteal cells of the corpus luteum, which is an essential factor in main- 

 taining the raised nutrition of the uterus in tbe early stages of pregnancy. 

 The evidence for these conclusions and for the internal secretion of the testes, 

 is fully set forth, and an account is given of the effects of castration. Two 

 chapters are contributed by J. Lochhead on the placenta and changes in 

 the maternal organism during pregnancy. Tbe more important phenomena 

 of parturition and lactation are described, and the causes determining lacta- 

 tion are discussed. The last three chapters deal with fertility and the causes 

 which influence it; the determination of sex, in which the leading hypotheses 

 and the observations on which tbey are founded are very throughly summa- 

 rized; and the phases in the life of the individual, in which growth, pu- 

 berty, menopause , senescence and death , and tbe phenomena accompanying 

 them are described. The whole book is remarkably thorough , and in cases 

 where there are divergences of opinion, impartial; it includes mention of work 

 which appeared almost up to the time of publication, and must be regarded 

 as an exceedingly valuable summary of what is known at the present time in 

 all matters connected with mammalian reproduction. 



Doneaster (Cambridge). 

 1756) Nemec, B. (Pflanzenphys. Inst. Böhm. Univ. Prag), Das Problem 



der Befruchtungsvorgänge und andere zytologische Fragen. 8°. 



532 S. 119 Abbild. 5 Taf. Berlin, Gebr. Bornträger. 1910. 



Den reichen Inhalt des Buches durchzieht als leitender Gedanke die Frage: 

 Ist eine Sonderstellung der Geschlechtszellen berechtigt oder können die sich 

 an ihnen abspielenden Vorgänge uns auch durch Erscheinungen von vegetativen 

 Zellen her verständlich gemacht werden? 



Von besonderer Wichtigkeit sind hierfür die Zell- und Kernfusionen, die 

 sich zuweilen abspielen, denn damit wird naturgemäß die Chromosomenzahl 

 erhöht, und es erwächst uns so die Möglichkeit nach Reduktionsteilungen zu 



