STJMMAKY OF CURRENT RESEARCHES 



RELATING TO 



ZOOLOGY AND BOTANY 



(PRINCIPALLY INVERTEBRATA AND CRYPTOGAMIA), 



MICEOSCOPY, Etc.* 



ZOOLOGY. 

 VERTEBRATA. 



a. Embryology, t 



Ovulation in the Rabbit.} — Walter Heape has studied the ovula- 

 tion and the degeneration of ova in the domestic rabbit. The doe only 

 permits coition when undergoing oestrus ; if the male be then withheld, 

 the ova are not dehisced, but degenerate in the ovary. Ovulation 

 usually occurs about 10 hours after copulation, but does not follow if 

 from any cause a sufficient supply of blood to the ovaries is interfered 

 with. The author describes the Graafian follicle, the maturation, the 

 ovulation, the corpus luteum, the degeneration of ripe follicles, and the 

 false corpus luteum. 



Maturation takes place about 9 hours after copulation ; two polar 

 bodies are rapidly formed after the supply of nutriment to the ovum is 

 cut off. About 10 hours after copulation the Graafian vesicle ruptures, 

 and the ovum, entirely freed from discus proligerus cells, is shot out 

 into the infundibulum, which now closely invests the ovary. The freed 

 ovum is incapable of assimilating nutriment, unless it be fertilised. 

 Spermatozoa are found at the top of the uterus horn about 2 hours after 

 copulation, close to the infundibulum in 4 hours. It is probable that 

 the rupture of the follicle is due to the stimulation of erectile tissue. 

 The corpus luteum is formed by the ingrowth of cells surrounding the 

 follicle, together with the follicular epithelium ; the ingrowth being at 

 one time apparently a forcible rush, before which the loosened epithe- 

 lium is driven. 



If a buck is withheld from a doe during several consecutive periods 



* 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, series B, lxxvi. (1905) pp. 260-8. 



