THE FERTILIZATION OF THE OVUM. 



FIG. i. Diagrams showing the process of fertilization according to different 

 authors. The first row (A, B and C), for Ascaris, according to Van Beneden ; 

 the second row, the same form, according to Boveri ; the third row for an Echinid, 

 according to Fol ; the fourth for Lilium, according to Guignard. 



