1901] . GAMETOGENESIS AND FERTILIZATION IN ALBUGO 253 
cells in many pteridophytes (Strasburger 1889). Normally, 
therefore, the production of pectin in Albugo is analogous to 
the so-called secondary effects of fertilization commonly seen in 
the higher plants, since it is an effect manifested by a cell other 
than those directly concerned in the act of fertilization. 
SUMMARY OF SECTIONS II AND III. 
The processes leading to zonation may be regarded as the 
differentiation of an ooplasm rich in trophoplasm. The nuclei 
pass outward, possibly to leave part of their kinoplasm outside 
of the ooplasm, in order to lessen the possibility of partheno- 
genetic development. The antheridial nuclei give evidence of 
heightened kinoplasmic content. 
The cell plate is formed, without the participation of the 
nuclei, by a rearrangement of alevolar planes. 
The simultaneous mitosis in gametogenesis is a phylogenetic 
reminiscence, and was of value in ancestral forms in increasing 
the number of gametes. 
No constant time relation is maintained between the phases 
of oogenesis and spermatogenesis, but each after its inception 
seems to proceed independent of the other. 
The orientation of the nuclear figure determines which, and 
consequently how many, primary oospheric nuclei shall enter 
the oosphere. This orientation seems to be merely accidental. 
The supernumerary nuclei are phylogenetically gametes, and 
their dissolution finds analogy in the Saprolegniaceae and Fuca- 
ceae, in Actinosphaeria, and in cases of physiological poly- 
spermy. 
The receptive papilla is the result of a softening of the 
oogonial wall by the oogonial contents, accompanied by high 
turgor in the oogonium. It is probably a vestigial character 
recalling an algal ancestry. It is a structure of the oogonium, 
and therefore is not homologous with the receptive spot, which 
is a differentiated region of the oosphere. 
The migration of the sperms from the antheridium is homol- 
ogous with the emptying of a sporangium, rather than with 
