Plaie XVII. 



(For explanation <it' aMireviations ami colours sec p. 370) 



Ail tlio l'if>nr('s arc tv.uisvovse sections of tlie embryos cut throivi>-li tlio levels 

 )iiark((l with riniiiei-als in small ty[)(! in the correspoiidiuü; surface views. 

 Fi(is. '>1-{J0 ai'c taken IVom the specimen represented in I'ig. 1. I'lic iiiosohlastic 



septum in Fig. öS is niagnitied in Fig. öd. 



Fig. (il is taken frona the specimen represented in Fig. 2, 



Fios. ()2-05 are „ „ ., ,. 8, 



. <i<i-ti7 .. „ „ „ ., 4, 



„ 68-Ü9 „ „ „ „ „ 5, 



„ 70-72 ., ., „ „ „ (5. 



Fu;. 71. An epihlastic cell iji tlie connection is here in division. 



l''ic,.s. 73-74 ;ire taki'ii horn the .specinaen represented in l''ig. 7, 



n 7:î-7S ., „ „ „ ,. „ 8. 



Fio. 7<S. An epihlastic cell is here in division. 



I'kt. 79 is tak'en h-oiu the specimen represented in Fig. 11. 



The dorso-ventrally elongated sero-amniotic connection is pi-essed down to a 

 horizontal position. 

 Figs. 80-82 are taken from the specimen represented in Fig. 16, 

 . 83-84 „ „ „ „ „ „ 21. 



The comiection of Fig. 83 is magnified in Fig. 84. 

 Figs. 8.')-87 are taken from the specimen of the twelfth day showing ]ici-f(H-ations 



in the sero-amniotic connection. 

 Figs. 88-89: Eepresent a stage nearly ecjual to that shown in Fig. .'j. The first is 

 anterior to the second by yV min. At the level given in Fig. 8H tlic anmion is 

 just closed. In these two figures nuclei are represented by white spots. 

 Fig. 90 Section Just in hoiu of the ailantois of au embryo, which is of the sanae 

 stage as that represented in Fig. 5. The point A is the lat(n-al angle of the 

 amniotic fold. 

 Figs. 92-93 : Sections of the specimen represented in Fig. 37, through the levels 

 marked witli the corresponding number on the latter. The points A, B, & C 

 inFig. 92 con-espond to the points marked witii the same letters in the 

 surface view. 



