ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 209 



from the contact to the reaction. The occurrence of respiratory 

 movements is dependent on the power already present of reflex move- 

 ment in response to stimuli on the skin, not the power of reflex 

 movements ou respiration. 



Little has been ascertained with regard to the sense of temperature 

 and the muscular sense ; the fact that mobility is increased by warmth, 

 and diminished by cold, of course proves nothing as to the sense of 

 temperature projierly so-called. The human foetus gives signs of 

 having feelings of taste two months before birth. The whole complex 

 of parts belonging to the ear is functionless before birth, as are also 

 the parts of the eye ; but the power of raising the eyelid is present ; 

 the eyes are not closed in the human embryo after the sixth month. 

 The conditions for the organic feelings are present several weeks 

 before birth ; pleasure and pain can be distinguished. 



The author finally puts the question, What is the actual state of 

 the embryo normally? He arrives by a series of arguments that 

 seem pretty conclusive when taken together, at the result, that its 

 state is normally like dreamless sleep or like the state of hibernating 

 animals ; it does not wake up from this state before birth except 

 momentarily, and then only when strongly stimulated.* 



Tail in Human Embryo.f — Eeferring to his previous communi- 

 cation as to the presence of supernumerary vertebrae in a human 

 embryo, I Prof. H. Fol announces that by anatomical reconstruction 

 of an embryo 8 • 1 mm, he has ascertained the existence of a back- 

 ward prolongation of the intestine from the point where the anus 

 will be formed. A similar condition has been found by Kolliker in 

 the embryo of the rabbit. In man it is especially interesting, since 

 the already distinctly marked position of the anus prevents any 

 mistake as to the fact that this " caudal intestine" is a transitory 

 structure. 



Spermatogenesis in Mammals.§— Herr Benda reports the exist- 

 ence of Ebner's spermatoblasts in all the mammals (rat, dog, guinea- 

 pig, rabbit, &c.) which he has examined. 



The lobate spermatogenetic elements are connected with a cell 

 which lies in the wall of the seminal tubule ; this condition appears 

 to be preceded by one in which elements whose nuclei are marginal 

 are connected with a " foot-cell," and this by a stage in which round 

 cells formed by cell-division lie on the processes of the " foot-cell." 

 Herr Benda differs from Merkel and Sertoli, who regard the " foot- 

 cell " as a fixed supporting cell, for he finds between the phase in 

 which the elements are separated from the " foot-cell," and that in 

 which new elements lie on these cells, a period in which the generative 

 columns derived from the wall-cells are alone developed. The processes 

 can only arise at the commencement of every spermatogenetic period. 

 In opposition to Merkel he finds that the essence of the change consists 



* Cf. Amer. Natural., xx. (1SS6) pp. 80-1, from Mind, No. xxxvii. p. 152. 



t Arch. Sci. Pbys. et Nat., xiv. (18S5) p. 5G6. 



X See this Journal, v. (1885) p. 781. 



§ Arch. f. Anat. u. Physiol. (Physiol. Abtli.) 1886, pp. 18G-7. 



Ser. 2.— Vol. VI. p 



