78 BOTANICAL GAZETTE [july 



time having lost definite form and become intimately associated with the 

 protoplasm of the host, yet many observations and experiments are arrayed 

 by the author in proof of its existence. Moreover, certain analogous states 

 have been observed in other organisms. Among the most striking instances 

 are Rozella and Woronina, belonging to the Chytridineae, and parasitic on 

 Saprolegnia. According to the studies of Cornu and Fischer, when these 

 plants penetrate the host they become diffused for a time in the protoplasm 

 of the cell, and are then quite unrecognizable. Afterward they assume the 

 usual form and produce spores. In accordance with this theory rust may be 

 checked by treating the seed in a manner to kill the mycoplasm. A change 

 of climate, conditions of growth, etc., may also cause the death of the 

 mycoplasm, which will account for the fact that seed from rust-infested 

 fields when taken to another locality or a distant country often gives plants 

 free from that particular kind of rust. 



In the third part of the paper the author discusses the various points 

 raised by different writers who have expressed an opinion upon the subject. 

 Only two American mycologists are mentioned, H. L, Bolley and M. A* 

 Carleton, The paper closes with a bibliography of works cited, naming over 

 forty authors and probably twice as many titles. — J. C. Arthur. 



