378 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Structure of the Functional Mammalian Ovary.* — Dr. C. H. Strata 
has made a detailed series of observations on the changes undergone by 
the ovary during adult life in Tupaia javanica , Sorex vulgaris , and Tarsius 
spectrum . In each case he had at his disposal a great number of speci- 
mens. He finds that in all cases there is distinct menstruation, but in 
Sorex there is no proof of an outflow of blood. In Tupaia, at least, the 
eggs are mature at the beginning of menstruation, and ready for fertili- 
sation at its end. The number of corpora lutea correspond to the number 
of eggs shed, and there is nothing to differentiate the corpus luteum 
menstruationis from the corpus luteum verum. If fertilisation take place* 
the follicles in the ovary undergo degeneration, and no mature eggs are 
produced till near the end of pregnancy. Not all the eggs shed into 
the oviduct are fertilised, so that the number of fresh corpora lutea i& 
no evidence of the number of embryos in the uteri. Where the period 
of heat is well-marked, as in Sorex, mature eggs do not seem to be pro- 
duced except at this period, the follicles undergoing degeneration (atresia)' 
instead of ripening. 
The paper is prefaced by an elaborate historical sketch of the ob- 
servations hitherto made on the mammalian ovary, and contains amass of 
detail in regard to its various structures. 
b. Histology. 
Peculiar Form of Protoplasmic Budding.|— Herr Martin Heidenham 
describes a peculiar appearance observed in the epithelial cells of the 
pregnant uterus in the rabbit. The material was fixed in sublimate,, 
and the author believes that the appearances described were the result 
of the pathological stimulus exerted by the fixing solution during the 
few moments which elapsed before the death of the cells. The appearance 
was as follows : — -The protoplasm of the cells became drawn out into 
finger-shaped processes, one of which projected from the surface of each 
cell. Not infrequently the end of each process was globular and slightly 
swollen. This globular region was radially striated, the striations sur- 
rounding a granular mass which the author believes to be the microcen- 
trum of the cell. From this microcentrum a fine axial thread could be 
traced leading down the process towards the nucleus of the cell. If the 
identification of the granules of the process with the microcentrum be 
correct, the present observations illustrate the intimate connection be- 
tween this structure and protoplasmic movements. It is probable also 
that the position of the microcentrum determines the area^in which 
such protoplasmic movements occur. 
Nuclei of the Bod-Cells in the Eetina.J — Dr. A. Schaper returns 
to a subject which he has previously discussed. In the cat, rabbit, horse* 
&c., the nuclei in the rod-cells of the retina are cross-str^ed, owing to 
the regular disposition of the chromatin. The same has been alleged, 
to occur in man, but it is certainly not the usual disposition, and the 
probability is that it does not occur in any case. It is suggested: 
* ‘Die gesohlechtsreife Saiigethiereierstock,’ Haag, 1898, pp. 1-67 (9 pis.). 
f Arch. Mikr. Anat.. liv. (1899) pp. 59-67 (1 pi.). 
[ J Anat. Anzeig., xv. (1899) pp. 534-8 (1 fig.). 
