22 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Delage's general view is that the agents which induce artificial partheno- 

 genesis act as temporary poisons. 



Artificial Parthenogenesis.* — C. Viguier notes that the develop- 

 ment or commencement of development of eggs which would not spon- 

 taneously develop, is now known to be induced by (1) changes in sur- 

 rounding temperature ; (2) mechanical excitation, notably shaking ; 

 (3) exposure to various solutions, which may have a directly chemical, 

 or osmotic, or catalytic action ; and (4) to the introduction of sperma- 

 tozoa of a different species from the ovum. 



Viguier has experimented with Splicer echinus, Toxopnwstes, and 

 Arbacia, and emphasises the absence or rarity of artificial partheno- 

 genesis under the above modes of treatment. Only the third mode 

 gave any positive results. 



Reappearance in Offspring of Lesions Artificially induced in the 

 Mother.f — A. Charrin, Gr. Delamare, and Moussu find that the progeny 

 of pregnant rabbits and guinea-pigs, subjected to laparotomy, some- 

 times show congenital hepatic or renal lesions (congestion, hemorrhage, 

 degeneration, &c). The state of the diseased organ in the offspring 

 is precisely analogous to that of the artificially deteriorated organ in 

 the mother. 



The authors conclude that " characters acquired by the mother may 

 be transmitted to the offspring. This transmission, this selective action 

 at a distance, this vital induction, this influence of a parent's organ on 

 the corresponding organ of the offspring, is due to the action of soluble 

 substances." Thus they explain the reappearance in successive genera- 

 tions of congenital distrophy of liver, kidneys, &c. That the phenomena 

 are in the strict sense facts of inheritance is another question. 



Note on Oogenesis in Mammals. J — Hans von Winiwarter dis- 

 cusses the so-called " Balbiani's body " (NebenJcern) in the oocytes of 

 man and rabbit. The Nebenlcern in the human ovum is an idiozome 

 and equivalent to a similar body in the oocyte of the rabbit ; but the 

 Balbiani's body of the rabbit's ovum is not an idiozome ; it is a quite 

 distinct and accessory chromatoid structure. 



Retrogressive Changes in Ovarian Follicle of Amphibians.§- 

 A. Biihler finds that these begin with two almost contemporaneous pro- 

 cesses : — a chromatolytic dissolution of the germinal vesicle, and the 

 penetration of follicular epithelium and some leucocytes into the ovum. 

 The epithelial cells have most to do with absorbing component parts of 

 the ovum, especially yolk and pigment, the dissolved results of which 

 are removed via the blood-vessels. While the whole is being reduced 

 in this way, there is an intrusion into the follicle of connective tissue 

 from the theca, and this, as shrivelling proceeds, replaces the degenerat- 

 ing follicular epithelium, which finally disappears into the stroma ovarii. 



Germ-Cells and Germinal Continuity. — John Beard read a paper 

 on this subject to the Royal Physical Society, Edinburgh, on November 24. 

 The following abstract is published in the billet. The germ-cells of 



* Comptes Rtndus, cxxxv. (1902) pp. 197-9. f Tom. cit., pp. 189-91. 



t Anat. Anzeig., xxi. (1902) pp. 401-7 (3 figs.). 

 § Morph. Jahrb., xxxi. (1902) pp. 85-103 (2 pis.). 



