9 8 



THK PHYSIOLOGY OF REPRODUCTION 



during oestrus are fertilised. I hiving pseudo-pregnancy the uterus 

 undergoes growth changes which relate chietly to the blood-vessels 

 and glands of the mucosa. 1 These increase in size, the whole organ 

 assuming a hist< domical appearance of great activity. Three weeks 

 after the beginning of pro<ostrous bleeding, the epithelial cells lining 

 the crypts and glands are columnar, and this condition remains until 

 about the end of the fifth week when the cells become cubical. The 



5 ft 



h 



' ViU_/,,, 



FIG. 17. Section through nuirosa of dog during ;i late stage of recuperation. 

 (From Marshall and Jolly.) 



///. c., Blood-vessfl : .N-/-., sprrniut<>/.<>a in cavity of gland. 



luinina of the glands contain a colloidal secretion and in tin- later 

 stages remains of desquamated epithelial cells. About the eighth 

 or ninth week from the beginning of " heat ' the capillaries begin 

 to break down and corpuscles are freely extra vusated in the 



1 Mai-shall and Hainan. "On tli> MMIS Cliangfs (n-.-nn-ing in the 



( icncrativc Organs and Mammary <Jland* "f tin- Nmi - I'l-.-^nant hog," !',<><. 

 Hi, if. Snr., 1',., vol. lx\\i\.. l!17. <'/. Keller. " I'lier den Man des Kiid>m.-ti-iiims 

 l.eim Hunde." .I/"//. //>/'?, v..l. cxviii., 1!M)!> ; and l>rahn, '' 1 >ie anatnuiis. -h.-n 

 Veriinderuiigeii am Qeachlechtaapparat nnsei-er Haiistii-re l.ei del P.runst mil 

 liesonderer lieriirksielitigung der Hiindin.'' //>">/. -/><.. pu //'//////</, I'erlin, 

 1913. 'Pliis memoir contains interesting comparative data. 



