48 K. MITSUKÜEI. 



Figs. 54-55. At various distances in front of Fig. 53. 

 Fig. 56. Median dorsal part of the Amnion in a section from the 



middle dorsal region of the Trionyx embr3o represented 



in Fig. 24. DD x 4. 

 Fig. 57. Median dorsal part of the Amnion in a section from the 



dorsal region of Trionyx embryo represented in Fig. 19. 



DDx4. 



Plate. VII. 



Fig. 58. Longitudinal section of an embryo from the same stage as 



that represented in Fig. 1. DD x 2. 

 Fig. 59. Transverse section of the embryo represented in Fig. 1. 



DD X 2. 

 Fig. 60. Longitudinal section of the Trionyx embryo shown in 



Fi^. 20. OCX 2. 



Fig. 61. Longitudinal section of a Trionyx embryo lOj days old. 



GG X 2. ^'"-^ 



Fig. 62. Longitudinal section of a Trionyx embryo 9 days old. 



GG X 2. *"'-^ 



Fig. 63. Longitudinal section of a Trionyx embryo IH days old. 



GG X 2. ^'''•' 



Fig. 64. Longitudinal section of a Clemmys embryo 4 days old 



with 16 mesoblastic somites. BB x 2. ^^^^-^ 



Fig. 65. Lorjgitudinal section of a Clemmys embryo 6 days old 



with about 20 mesoblastic somites. BB x 2. ^^^^"^ 



Fig. 66. Longitudinal section of a Clemmys embryo 9 days old. 



BB X 2. ^^""'^-^ 



