SUMMARY OF CURRENT RESEARCHES 



RELATING TO 



ZOOLOGY AND BOTANY 



(PRINCIPALLY INVERTEBRATA AND CRYPTOGAMIA), 



MICEOSCOPY, Etc.* 



ZOOLOGY. 



VERTEBRATA. 

 a. Kmbryolog'y.t 



Mendelian Action on Differentiated Sex.| — 1). Berry Hart has 

 made an interesting inquiry into the relation of Mendelian inheritance 

 and sex. It is sometimes urged that Mendelism does not apply in 

 normal human development, but the author attempts to show that it 

 really does, and his argument is somewhat as follows : — 



In the male and female genital tract there are present the potential 

 organs characteristic of the developed special sex, and also traces of the 

 opposite sex. Thus the adult human male genital tract contains not 

 only the testes and phallus, but also the Miillerian hydatid Of the 

 testes and the prostatic utricle, the representative of the hymen ; while 

 the female genital tract has the characteristic ovaries, uterus, and vagina, 

 but also the epoophoron and its duct, the representative of the epi- 

 didymis and ductus epididymis of the male. These may be termed the 

 potent and non-potent elements of the tract, but they may also be 

 looked on as dominant and recessive in Mendel's sense. Thus the 

 phallus and testes are dominant ; the hydatid testes and prostatic 

 utricle recessive ; while in the same way the ovaries, uterus, and vagina 

 are dominant, and the epoophoron recessive. All the parts making up 

 the associated genital tract are classified in the same way, but the above 

 part of this classification is all that is necessary for the author's argu- 

 ment. Weismann's terminology is used to a certain extent — viz. 

 " determinants " for the elements in the zv^ote that are causal to the 

 results or determinates in the fully developed animal. 



* The Society are not intended to be denoted by the editorial " we," and they 

 do not hold themselves responsible for the views of the authors of the papers 

 noted, nor for any claim to novelty or otherwise made by them. The object of 

 this part of the Journal is to present a summary of the papers as actually pub- 

 lished, and to describe and illustrate Instruments, Apparatus, etc., which are 

 either new or have not been previously described in this country. 



t This section includes not only papers relating to Embryology properly so 

 called, but also those dealing with Evolution, Development, Reproduction, and 

 allied subjects. 



X Proc. Roy. Soc. Edinburgh, xxix. (1909) pp. G07-18 (3 figs.). Also in extenso, 

 Edinburgh, 1909, pp. 1-11 (3 figs.). 



