PLATE IL 



fClLelon ia ca ou au a . ) 



FiG. 5«. — Ventral view of the embryo of Clielonia caoudiia represented in Fig. 5. 



aa X 2 (B 11 ^^) 



Fig. 8^/. — Ventral view of the embryo of Ckeloiiid caoiuuia represented in Fig. 8* 



««X2. (B12^) 



(Clemmys japonica.) 



s 

 Fig. 9. — Dorsal view of an embryo of Clemmys jajxmica taken out 3 days after it 



deposition. The amnion is just arising, and the medullary canal is open 



throughout. See p. 25. aa x 2. (XXXIV 



Fig. 10. — -Dorsal view of an embryo of Clemmys japoinca with 5 mesoblastic somites, 

 taken out 4^ days after its deposition. The amnion covers a little less 

 than half the length of the embryo. See p. 25. Sections in Series 

 III. (PI IV). aa X 2. (XXXXIX) 



Fig. 11. — Dorsal view of the posterior part of an embryo of Clemmys japonica with 

 6-7 mesoblastic somites, taken out 5^ days after its deposition. The 

 amnion leaves only a small posterior portion of the embryo still exposed. 

 The medullary canal is still open at the posterior darkened portion. The 

 two white lines which diverge posteriorly from the mid-dorsal region 

 are the internal limits of the extra-embryonic cavities. See p. 25. 

 J.4x2. (L0) 



Fig. 12. — Dorsal view of the posterior part of an embryo of Clemmys jajwnica with 

 6-7 mesoblastic somites, taken out 4 days after its deposition. The 

 amnion leaves the posterior part still exposed. The medullary canal is 

 now entirely closed. The white diverging lines on the mid-dorsal 



region are the internal limits of the extra-embryonic cœlomic cavities. 

 Seep. 26. AAx2. (LV) 



Fig. 13. — Dorsal view of the posterior part of an embryo of Clem^iys ja/ioiiica with 

 6-7 mesoblastic somites, taken out 6 days after its deposition. The 



