ox THE FOETAL MEMBRANES OF CHELOXIA. 49 



Plate. VIII. 



Fig, 67. Surface view of a Clemmys embryo 28 days old. Seen 

 from outside the serous envelope. x 4^. ^''^^'•* 



The upper transparent membrane is the serous envelope» 

 The lower opaque membrane with blood-vessels is the 

 yoîk-membraiie. Between these two membranes are 

 placed the enihnjo, the allantois &c. Different divisions 

 of the allantois are sufficiently explained in the text. 

 The white line close to and parallel with the median 

 dorsal line oi the embryo is the sero-amniotic connec- 

 tion. : traced posteriosly, it bends sharply to the left, 

 this short liml) being the remnant or proximal part of 

 the posterior tube of the amnion. Over the posterior 

 part of the embryo, is a clehcate, irregularly curved 

 white tube : this is the distal part of the posterior tube 

 of the amnion with its horse-shoe sha[)ed posterior 

 opening. It has no connection with the proximal part. 



Fig. 68. Dorsal view of a Clemmys egg, with the embryo, the fetal 

 membranes, and the yolk-sac. About 40 days old. x 2. 



(LXSII.) 



Fig. 69. Side view of a Clemmys egg with the embryo, the fetal 

 membranes, and the yolk-sac. 51 days old. Nat. size. 



(lxxiii.) 



Fnj. 70. Ventral view of a Clemmys egg with the embryo, the foetal 

 membranes and the yolk-sac. 55 days old. Blood-vessels 

 on the yolk-sac omitted. Nat. size. a-ssv.> 



B'ig, 71. Dorsal view of a Clemmys embryo, shortly before hatching 

 with the fœtal membranes. 45 days old. ^''^'^•* 



