460 BOTANICAL GAZETTE [DECEMBER 
Fic. 5.—Early stage of synapsis in embryo sac mother cell. 
Fic. 6.—Later stage of same. 
Fic. 7.—Part of an apparently continuous spirem, just after synapsis. 
Fic. 8.—Later stage of same, showing divided granules. 
Fic. 9.—Still later stage, showing split spirem. 
Fic. 10.—Still later stage; the two halves have come together and the spirem 
has become looped. 
Fic. 11.—Chromosomes derived from loops shown in jig. 10. 
Fic. 12.—Later stage of same. 
Fic. 13.—Still later stage. 
Fic. 14.—Still later stage; the two halves have come together. 
Fic. 15.—Longitudinal section of a metaphase of the first division of embryo 
sac mother cell. 
Ic. 16.—Anaphase of same. 
Fic. 17.—Early stage in formation of daughter nuclei. 
Fic. 18—Two-nucleate embryo sac, showing cross-wall separating the two 
nuclei. : 
Fic. 19.—Slightly older embryo sac. 
Fic. 20.—Embryo sac showing same stage as last. 
Fic. 21.—Nuclei of a two-nucleate sac dividing; remnant of dividing wall 
still present. 
Fic. 22.—Four-nucleate sac ; one nucleus separated from the other three by a 
wall. 
Fic. 23.—Later stage; wall was disappeared. 
Fic. 24.—Four nuclei have divided to eight; no cell plates on the spindles; the 
sister nuclei in micropylar end. 
Fic. 25.—Later Stage; the two sister nuclei still in micropylar end. 
Fic. 26.—The eight nuclei have just divided to sixteen; cell plates seen on the 
spindles. 
Fic. 27.—Later Stage; cell plates shown in last figure have grown into walls 
cutting off eight nuclei against the embryo sac wall and leaving eight free in me 
cytoplasm. 
Fic. 28.—A mature ovule; the embryo sac contains sixteen nuclei; , pollen 
tube with nuclei; ¢, tapetum; 7, in ent. 
Fic. 29.—Embryo sac with fertilized egg and nuclei fusing to form the wee 
Sperm nucleus; e, egg with fusing nuclei; 7, pollen tube; s, nucleus with : 
Position of a synergid; d, peripheral nuclei which will degenerate; f, nuclei fusing 
to form endosperm nucleus. 
Fic. 30.—Later stage of fusion in male and female nuclei. 
Peperomia ottoniana 
Fic. 31.—Four-nucleate sac; one nucleus cut off and surrounded by dense 
; ae arse 
Fic. 32.—Later stage; the wall a: g ‘4 1 ~~ - PI 
