294 



EMEETOLOGT. 



cicatrice (fig. 321) ; the whole process is very similar to 

 that which occurs among the mammalia when the Graafian 

 vesicle gives way and the corpus luteum is formed. The 



oviduct attaches it- 

 self, by a kind of 

 suction, by its patu- 

 lous infundibulum 

 or bevelled abdomi- 

 nal end to the cap- 

 sule which contains 

 the ripest ovum, 

 and receives this as 

 it escapes. From 

 this point the ovum 

 makes its way mov- 

 ing spirally along 

 the muscular ovi- 

 duct, which is now 

 very much enlarged, 

 highly vascular, and 

 pouring out from its 



mucous surface the 

 Fig. 322. Ovary of the fowl, with vitelli or a lk umen w hi cn is 

 yolks, ripe and approaching maturity: a, a ,. 

 ripe yolk within its calyx or cup, the cicatrice 



of which, bj b, is seen as a transverse non-vascu- yolk in the different 

 lar streak ; c, c, smaller yolks, with the vascular 

 rete of their cups and their cicatrices ; d, a 

 calyx empty, the part having given way along 

 the line of the cicatrice smaller yolks (e) are 

 enveloped by calices so transparent that the ci- 

 catricula is seen through them. 



layers but just de- 

 scribed. The forma- 

 tion of the chalazse 

 is a consequence of 

 the rotatory motion 



upon its axis which 

 the ovum receives in the oviduct, and of the setting of the 

 albumen. The lower part of the oviduct is dilated into a 

 receptacle for the egg, and here are added the membrane of 

 the shell, and finally the shell itself, the milky calcareous 

 fluid secreted by this part being precipitated upon the egg in 

 crystals, which are at first isolated, but very soon run together 

 and cohere. The egg remains over twenty-four hours in the 

 receptacle. The germ at the first entrance of the egg into the 

 oviduct has already assumed the appearance proper to it at any 



