104 THK PHYSIOLOGY OF REPRODUCTION 



size and number, producing uterine congestion. These changes occur 



Uth in tin- cotyledonary papillae and in tin- intervening tissue 

 around the bases of the papilla-. 



l',rin,l ,.f A-*/,-/*/-/ /.,/,. -The congestion is followed in raost 

 oases by the breaking down of some of the vessels. Very frequently 

 tin- lir.-t extravasation takes place from vessels situated immediately 

 below certain parts of the stroma where the nuclei are most thickly 

 distributed. Leucocytes are extravasated along with the red cor- 

 puscles, but there is no evidence of the existence of wandering cells 

 apart from those which are derived appaiently from the broken-down 

 vessels. The blood tends to collect below the epithelium. Bleeding 

 into the uterine cavity may occur, but is not invariable. A few 

 epithelial cells are sometimes torn off (presumably in places where 

 blood is poured out into the cavity), but destruction even to this 

 extent does not necessarily take place. Denudation of the stroma 

 has never leen observed. It would seem that the severity of the 

 pru.i->trous process tends to diminish with each successive dkr-strous 

 cycle in the In-ceding season, and that sometimes in a late prooestrum 

 the period of destruction is never reached, the congested vessels 

 sulidin<; without undergoing rupture. Bleeding, when it does 

 occur, appears to be more frequent in the cotyledonary papilla- 

 than lietween them, and is commoner in the large papillae than in 

 the smaller ones. 



Ka/xander 1 appears to have been the first to detect extravasated 

 blood in the sheep's mucosa. Subsequently Bonnet' 2 has noted 

 uterine bleeding in various Iluminants, as well as in the mare and 

 sow, and Kolstei ' has made similar observations (<;/'. also Emrys- 

 Boberts, see p. 43). K \\ai-t also has described pron-strous extravasa- 

 tion and the piesence of ha-matoidin crystals in the uterus of the 

 mare. (Jlandular activity during heat was also noted. 1 



ill Period qf Recuperation* Th-- sheep's prou-strum may he said 

 to end with the period of destruction, the entire process probably 

 lading for not longer than one or two days, its exact duration 



tiding upon its severity. <I>tius itself, which occurs during the 

 beginning of the period of recuperation, sometimes occupies only a 

 few hours. 



In those place- \\here Meeding into the cavity took place in the 



ding period the epithelium is renewed, apparently from the 



1 K;i7.zan<liT, " riM-r ili.- I'ijriin-iitat i..n d.-r I 't-i in- lil.-imliiiut des Schafes," 

 .\r,-l,.f. .\Hi;: A, "if., v,,]. xxxvi., I- 



: I'x.i.ii.-t. aiti. ! in Kll.-nl..-i -, i '> I', ,,//,/>,/,. /'/ /v ,- ;/,, ;,, ,/,.,- 



'. alx. Kll.-nlKT^cr^s article in same volume. 



IT Kciintnis- d.-r Kinbryotrophe bei Indeci- 

 902. 



the ] ' '. .'Inj.!!!.-!.! nf Illf Hn]S.-," 



v.,1. li.. - 



