288 Journal of Agricultural Research voi. iv, no. 4 



closely clustered here than in the remaining contents of either the egg 

 or the antheridium (PI. XLVII, fig. 6). This dense clustering indicates 

 that the presence of mitochondria in fertilization is not merely acci- 

 dental and invites speculation as to their function. Their orientation 

 at the periphery in the vegetative mycelium, and more especially in the 

 zoospores, suggests that they may be responsive to light stimulus, and 

 their accumulation in the presporangia and sex organs may indicate a 

 nutritive function. The evident close philogenetic relationship of the 

 fungus to algal forms perhaps supports the view that they are plastids, 

 possibly degenerate chloroplasts. Their participation in fertilization 

 raises a query as to whether they may not be charged with some part 

 in the transmission of hereditary characters. A more novel and very 

 interesting suggestion recently proposed to the author is that these 

 bodies may be liquid crystals, and that, if this be true, a study of their 

 origin and organization may lead to an understanding of the physical 

 link which binds life to nonliving material; that in them we may dis- 

 cover, evolving from the inorganic and nonvital, that combination of 

 physical and chemical properties with matter which characterizes life. 



Following fertilization, food vacuoles appear in the cytoplasm (Pi. 

 XLVIII, fig. 6, 7, 10) and then gather in a mass at the center (Pi. XLVII, 

 fig. 3, and XLVIII, fig. 4). This crowds the fused nucleus from its 

 position and leads to the development of a cytoplasmic zone about the 

 central lypoid body (PI. XLVI, fig. 12, and XLVII, fig. 3). In the 

 meantime a thick spore wall has developed. There is at first a lighter 

 zone between the cytoplasm and the wall (PL XLVI, fig. 19, and XLVII, 

 fig. 3), but this gradually disappears, evidently by the shrinking and 

 contraction of the wall (PI. XLVI, fig. 12, 20). 



The fused nucleus embedded in the cytoplasmic zone at first contains 

 two nucleoli located at the poles (PI. XLVII, fig. 3). These eventually 

 disintegrate, but before doing so they migrate from the polar positions 

 into the body of the nucleus (PI. XLVI, fig. 5, a, 6, c, 12, 20). 



Another interesting phenomenon was observed in scores of cases — in 

 the fused nucleus only and in material from but two lots, so that the 

 work on this point can not be regarded as complete or as thoroughly 

 established as is desirable. Owing to the pressure of other duties, how- 

 ever, the studies are not to be continued, and the observation is recorded 

 here in the hope that it may be of value to other interested workers. 

 During the progress of the changes of the nucleoli mentioned in the 

 preceding paragraph, a single small body appears in contact with the 

 nuclear membrane at one end (PI. XLVI, fig. 5, a). Shortly following 

 this, two bodies are present, one of which moves around to the opposite 

 pole (PI. XLVI, fig. 5, 6, c, d, 19, 20). The position of the body suggests 

 a centrosome. 



Following the stages already discussed, there occurs a division of the 

 nucleus (PI. XLVII, fig. 7), giving rise to two nuclei which come to full 



