COMPARISON OF OVARIES 



'1ABLI-: I 



Biifo CO gnat lis Say 



NUMBER MKAN OP BODY 

 OF VOLUMKS IN 



SPECI- CC. WITH 



MENS STANDARD ERROR 



MEAN Ol- OVARY MEAN OVARY RANGE OF 



VOLUMES IN VOLUME PER- OVARIAN 



CC. WITH CENTAGE OF PERCENTAGES 



STANDARD ERROR MEAN BODY 

 VOLUME 



Biifo ti'oodhoiisii woodhotisii (Girard) 



vJUMBER MEAN OF BODY 

 OF VOLUMES IN 

 SPECI- CC. WITH 



MENS STANDARD ERROR 



MEAN OF OVARY MEAN OVARY 

 VOLUMES IN VOLUME PER- 

 CC. WITH CENTAGE OF 

 STANDARD ERROR MEAN BODY 

 VOLUME 



RANGE OF 



OVARIAN 



PERCENTAGES 



Microscopic Structures of the Ovaries 



Viewed microscopically, the ovary of a young toad is a double-walled sac 

 in which darkly stained nuclei of the wall itself and many primordial germ 

 cells are visible. Cross-sections through capillaries and a few larger blood 

 vessels are also to be seen, but the peritoneum which normally covers the en- 

 tire gonad cannot be demonstrated and is therefore presumed to be lost 

 during the preparation of the sections. 



A follicular envelope covers each developing oocyte and is its means of 

 attachment to the ovarian wall. The membrane, consisting of oogonial cells 

 whose oogenesis into mature germ cells has been sacrificed for the good of 

 the one cell which does undergo development in each cyst, is typically incon- 

 spicuous in yolky eggs; and in the gonads of B. cognatus and B. w. wood- 

 housii, it consists of only one to three layers of flattened cells. The zona pei- 

 lucida is a clear membrane immediately within the follicular envelope. It 

 can be seen in cells of B. w. ivoodhousii as small as 0.18 mm. in diameter 



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