44 K. MITSUKÜßl. 



Fig. 10. Posterior tube of the Amnion higlily convoluted, from 

 a Clemmys embryo 14 days old. aa x 2. ^'''"'•^ 



Fkj. 11. Dorsal view of a Clemmys embryo, 10 days old, 6^^ mm. 

 long. Enlarged about 17 times. ^"'"'^ 



Fig. 11a. Ventral View of another embryo from the same deposit. 

 Enlarofed about 17 times. 



Fig. 12. Semi-diagramatic view^ of the posterior constriction of the 

 AUantois in a Clemmys embryo 31 days old, seen from 

 outside the serous envelope, ca x 7. ^"'^'^ 



Fig. 13. Two Clemmys embryos 18 days old. Slightly enlarged. 



(xxxxv.) 



Fig. 14. Dorsal view of a Clemmys embryo whose amnion is open 

 toward the left. '^^^""•' 



Fig. 15. Posterior tube of the Amnion disappearing. From a 

 Clemmys embryo 13 days old, 8 mm. long. 



Plate. III. 



Fig. 16. Dorsal view of a Trionyx embryo 34 days old. a« x 2. 



(126.) 



Fiq. 17. Dorsal view of a Trionyx embryo o.i It y old, 3 mm. 



long, witli 5-6 mesobl. somites, aa x 2. 



(128.) 



Fig. 17a. Ventral view of the same. 



Fig. 18. Dorsal view of a Trionyx embryo 74 days old, 3t\ mm. 



long, with 7-8 mesoblastic somites, aa x 2. 



(141.) 



Fig. 19. Dorsal view of a Trionyx embryo 8^ days old, 4 mm. 



long, aa x 2. ^'"'-^ 



Fig. 19a. Ventral view of the same, aa x 2. 



Fig. 20. Ventral \'iew of the posterior part of a Trionyx embryo 



