Plate VI. 



Arabic numerals placed between every two sections indicate the number 



of sections that intervene between those two (exclusive). 



Certain marks on the left of each section are for the identification of the 



sections and do not concern the reader. 



Series VII. a. — Section through an embryo of Triony.c japonicas taken out 7Ä days 

 after deposition. Surface view in Fig. 24 (PI. II), in general appear- 

 ance very mncli like Figs. 22 or 23. For detailed description see p. 50. 

 CCx2. (155 0) 



Series VIII. a-^. — Sections through an embryo of Tiiunyx japonicus with about 13 

 mesoblastic somites, talcen out dh days after deposition. Surface view 

 given in Fig. 25 (PI. III). For detailed description see p. 51. CC'x 2. 



(151 ffl) 



Series XII. â-j. — Sections through an embryo of Tiiunyx japonicus with about 15 



mesoblastic somites, taken out 10^ days after deposition. Surface views 



given in Figs. 2G (PI. Ill), and 26r/ (PI. II). For detailed description 



seep. 64. CC'x2. (157 0) 



Co^Z. '=Extra-embryonic cœlomic cavities. 



