sae 
1901 | GAMETOGENESIS AND FERTILIZATION IN ALBUGO 95 
as to provide daughter structures equal in number to the nuclei 
which are to be formed. Considering the coenocentrum asa 
source of nutrition, the phenomenon of chemotaxis here as 
affecting the position of the nuclei is quite parallel to that 
exhibited so abundantly in animal cells, where the nuclei wander 
toward the source of nutritive supply (Korschelt 1889). The 
development of the pseudopodium-like structure also has its 
analogy in the animal cell, where the nucleus becomes amceboid 
or protrudes many pseudopodia in order to enlarge its absorptive 
surface (Korschelt 1889). In the nucleus under consideration 
the nature of the nutriment may render it more advantageous 
to penetrate by means of one sharp projection. While many 
plants possess cells having very irregularly shaped nuclei, 
é. g. endosperm cells of Zea, epidermal cells of Allium, Hya- 
cinthus (Zimmermann 1896), amaeboid movements are much 
more rare in plants than in animals. Kohl (1897) by the action 
of asparagin has incited such movements in the nuclei of the 
cells of Elodea and Tradescantia, and considers them compa- 
rable with the phenomena observed by Korschelt (1889). This 
also throws light on the behavior of the nuclei in Albugo. Kohl 
considers with Korschelt that the amceboid movement stands in 
direct relation to the heightened exchange between nucleus and 
cytoplasm. 
The coenocentrum may in a sense be likened to some of the 
so-called yolk nuclei, or Dotterkern of animal eggs. In A. But 
(Stevens 1899, fig. 69) and in A. candida (Davis 1900, fig. 2) 
there is slight indication of radiate structure which somewhat 
resembles the figures of Munson (1898) illustrating the yolk 
nucleus of Limulus. The structures agree in having nutritive 
functions. In certain cases, as in Limulus and the newt (Jordon 
1893), the yolk nuclei seem to develop directly from the cyto- 
plasm, and in this further resemble the coenocentrum. A com- 
parison of these structures emphasizes the fact that protoplasm 
in diverse organisms under certain conditions may become simi- 
larly differentiated for the performance of particular functions. 
Concerning the antheridial tube there is but little to add. 
