410 The Botanical Gazette. [ December, 
cells of the egg-apparatus, which lie side by side occupying 
the whole tapering anterior end of the embryo-sac, are the 
synergidae; at their lower extremity, extending nearly across 
the sac, lies a larger rounded cell, the oosphere. In further 
development, as found in fig. 23, the embryo-sac becomes 
very much swollen, which is a characteristic feature both be- 
fore and after the process of fertilization. But fertilization 
in this case has not yet been accomplished, as the perfectness 
of outline of the synergidae amply testify. The upper vacuole 
of the preceding figure shows a contraction toward the upper 
extremity of the embryonal sac and is more oval in outline. 
At this stage, also, the upper polar nucleus exhibits retarded 
action in its descent toward its counterpart from below, in 
many cases refusing descent till after or about the fertilization 
period. 
To trace the embryonal sac in its further development 
would result in recounting what, already, is very familiar to 
many botanists. 
Summary.—\. The calyx appears second in order of suc- 
cession of the floral whorls. 
II. The syngenesious anthers seem to be united structurally. 
III. The upper polar nucleus shows a slow descent in unit- 
ing with the lower one to form the endosperm nucleus. 
IV. Compared with Strasburger’s study of Senecio the fol- _ 
lowing differences were observed: 
1) The antipodal cells occur in no regular order, and 
as far as my investigations went, were never 
found arranged in a single longitudinal row. 
(2) No more than four antipodal cells could be discov- 
ered, always naked and having no cross walls. | 
(3) The oosphere, as far as could be determined, failed 
to occupy the whole diameter of the embryo-sac. 
(4) The nuclei of the cells composing the egg-appa- 
ratus seemed always to occupy an almost central 
position. 
(5) Vacuoles were seldom seen in the synergidae. 
All figures illustrating the development of parts given are 
from sections supposed to pass through the center of the 
tissue which they represent. 
All material used was fixed in 1 per cent. chromic acid 24 
hours, thoroughly washed, stained zz ¢ofo with alum carmine 
24 hours, again washed and dehydrated; then taken through 
* 
