PLATE 9 
EXPLANATION OF FIGURES 
112 Sperm-vesicle in egg, one hour and fifteen minutes old. This may now 
be called the ‘male’ pronucleus. 
113 Egg from the lumen of the ovary showing the spindle of the first miotic 
division. >. 3000. 
114 First polar body of an egg just spawned. X 3000. 
115 to 116 Two pronuclei found in one egg, two hours and fifteen minutes old. 
< 3000. 
117 Egg two hours and fifteen minutes old; h., transverse section of a hair of 
the pleopod with the shell of the egg wrapped part of the way around it; 7., 
pronucleus, probably the male; v., vitelline membrane. X 320. 
118 to 119 Egg four hours old, showing the pronuclei. Figure 118, X 366; 
figure 119, X 320. 
120 Egg six hours old, showing the pronuclei side by side in the center of the 
egg. X 320. 
121 Diagram of the ovary, the seminal receptacle and oviduct. The latter 
turned to one side so as to bring it in the same plane with the rest of the ovary; 
c., portion of the seminal receptacle lined with chitin; g., glandular portion of the 
seminal receptacle; 0., opening between the glandular and chitinous portion of 
the receptacle; 9d., oviduct. Natural size. 
122 Seminal receptacle at the time of molting; c., chitinous portion; g., glandu- 
lar portion. Natural size. 
200 
