304 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 31) Ser. 



S. simplex where this was especially studied, and of which 

 a preliminary account has already been published (Camp- 

 bell, 1899), tn i s * s especially noteworthy. Before fertiliza- 

 tion (fig. 12) the antipodal cells are extremely inconspic- 

 uous, but almost immediately after fertilization has been 

 effected they rapidly increase in bulk, and at the same time 

 show other marked evidences of active growth. The cyto- 

 plasm becomes more coarsely and densely granular, and 

 the nuclei enlarge to several times their original size and at 

 the same time take up stains much more readily than before 

 (fig. 26). As the antipodals increase in size they project 

 strongly into the cavity of the embryo-sac and form a con- 

 spicuous nearly hemispherical body. The three original 

 cells now rapidly divide until finally a very large mass of 

 cells (fig. 30) results, probably larger than in any other 

 Monocotyledon. The number of antipodal cells may finally 

 exceed 150, a number greater than that yet recorded for 

 any other Angiosperm. 



In position and general appearance the group of antipodal 

 cells most nearly recalls that of many Gramineas (Hof- 

 meister, 1861 ; Fischer, 1880, etc.). An important differ- 

 ence is that in the latter the development of the antipodal 

 complex is completed previous to the fertilization of the 

 egg. The method of its development, however, is very 

 similar in the two cases. 



The embryo-sac in those grasses which have numerous 

 antipodal cells has at first the ordinary number, three, and 

 these subsequently divide to form the larger number ulti- 

 mately developed. Hofmeister (1861) states that in the 

 Triticeal the number may be 6-12 and Kornicke (1896) 

 found 36 or more, a large number, but very much less 

 than the normal number finally developed in Sparganium 

 simplex. 



The first division of the nuclei of the antipodal cells 

 occurs shortly after the first division of the primary endo- 

 sperm-nucleus. Following the first division, the increase in 

 size of the antipodal cells and the divisions proceed rap- 

 idly, while the endosperm at this stage remains slightly 



