308 N. M. Stevens. 



Fig. 21. Longitudinal section of adult, showing sperm-duct {sd) slightly open 

 to the exterior. 2 mm. -4. 



Fig. 22. Cross-section of adult ovary, showing an egg (o) in the oviduct (od)' 

 B. and L. ^-A. 



Fig. 23. First polar body and second polar spindle of an egg free in the ovary- 

 2 mm.-12. 



Fig. 24. Two pronuclei of egg free in the ovary. D-4. 



Fig. 25. First segmentation spindle of free egg. 2 mm. -4. 



Fig. 26. Second seg. spindle of free egg. 2 mm.-4. 



Fig. 27. Section of egg in 8-cell stage, free in the ovary. D-4. 



Fig. 28. 'Besondere Korper' of same egg as Fig. 24. 1.5 mm. -4. 



