82 ARTHUR DENDY. 



Figs. 8 — 14. — Transverse sections of embrjo 58, arranged in order; drawn 

 under Zeiss A, ocular 1. 



Fig. 8. — Tiirougli the blastoderm in front of the embryo, showing tlie 

 large coelomic space in the mesoblast (P. C). 



Fig. 9. — Through the anterior portion of the embryo lying freely above 

 the blastoderm. 



Fig. 10. — Through about the middle of the embryo, showing the alimen- 

 tary canal still widely open below. 



Fig. 11. — Through the medullary plate and primitive groove. 



Fig. 12. — Through the primitive streak just in front of the blastopore. 



Fig. 13. — Through the blastopore. 



F'ig. 14. — Through the primitive streak just behind the blastopore. (This 

 figure includes part of the area opaca ou each side, which is omitted 

 from the others). 



Figs. 15—34. Stage E. 



Fig. 15. — Embryo 56, upper surface, with portion of surrounding blasto- 

 derm ; drawn from spirit specimen as an opaque object, x 10. (The an- 

 terior portion of the embryo now lies beneath the blastoderm of the area 

 pellucida, through which it is seen.) 



Fig. 1G. — Embryo 56, seen from below after removal of nearly the whole of 

 the sub-embryonal membrane, showing the anterior half of the embryo pro- 

 jecting freely beneath the blastoderm of the area pellucida ; drawn as before. 

 X 10. 



Fig. 17. — Embryo 56, seen from above as a transparent object, the front 

 half siiowing through the blastoderm of the area pellucida; after staining with 

 borax carmine and clearing in oil of cloves. Zeiss A (with the bottom lens 

 removed), ocular 1. 



Fig. 18. — Embryo 64, seen from above, with portion of surrounding blasto- 

 derm ; drawn from spirit specimen as an opaque object. X 10. 



Fig. 19. — Embryo 64, seen from below after removal of the sub-embryonal 

 membrane from beneath the anterior end of the embryo, while the posterior 

 part is concealed by this membrane and the adherent yolk ; drawn as before. 

 X 10. 



Fig. 20. — Embryo 64, seen from above as a transparent object, after staining 

 with borax carmine and clearing iu oil of cloves. The front part of the embryo 

 is seen through the overlying blastoderm. Zeiss A (with the bottom lens re- 

 moved), ocular 1. 



Fig. 21. — Embryo 64, anterior end seen from below, as before. 



Figs. 22 — 32. — Transverse sections of embryo 56 arranged in order; drawn 

 under Zeiss A, ocular 1. (In Figs. 23 — 26 the overlying blastoderm is 

 omitted.) 



Fig. 22. — Through the head iu front of the alimentary canal. The over- 

 lying blastoderm {A. F.) is shown above. 



