30 



PRELIMINARY ACCOUNT, 



[CHAP. 



to the body this space may be called the pleuroperitoneal cavity ; 

 but outside the body it runs up into either amniotic fold, and 

 also extends some little way over the yolk. 



D represents the tail end at about the same stage on a more 

 enlarged scale, in order to illustrate the position of the allantois 

 al (which was for the sake of simplicity omitted in (7), shewn as a 

 bud from the splanchnopleure, stretching downwards into the pleu- 

 roperitoneal cavity^. The dotted area representing as before the 



