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MISSOURI BOTANICAL GARDEN 



obtaining 



the fungus and its relation to the sporange-like structures 

 which Woronin and Moller considered as spores. Brunchorst 

 found that the content of the sporange segments into several 

 parts which he considers as spores. In the longitudinal sec- 

 tion he points out three distinct stages through which the 

 fungus passes in its development. He regarded the fungus 

 as distinct from Schinza and Plasmodiophora and considered 

 it a new genus, naming it Frankia subtilis, though admitting 

 that the fungus varies morphologically in different host 

 plants. 



Frank (9, 10), in his first contribution, sets forth some 

 peculiar views in regard to the fungus, considering the tuber- 

 cles as normal growths for the transitional storage of proteid 

 material. He mentions the vesicles and the various changes 

 which they undergo. In a later publication he revises his 

 former views and in many respects corroborates the conclu- 

 sions of Brunchorst. He did not succeed in 

 growths from cultures but describes very clearly the inter- 

 cellular infection, the effect of the fungus on the cell and its 

 nucleus, and the symbiotic relationship of the host cell and 

 the fungus. However, he did not believe with Brunchorst 

 that the vesicles are fruiting bodies with the dividing con- 

 tents comparable to spores. As the most appropriate name 

 for the fungus Frank proposed "Ernahrungsphysiologische 



Mycorrhiza." 



Atkinson (1) is the first who investigated the root-tuber- 

 cles of Ceanothus americanus, which were discovered in 1890 

 by Dr. W. J. Beal in Michigan. On examining fresh ma- 

 terial he found the organism producing structures closely 

 allied to that which is found in the tubercles of Alnus, 

 Elaeagnus, and Myrica, hitherto so well known in Europe. 

 He presented in his paper an accurate description of the in- 

 dividual tubercles as regards color, shape, size, method of 

 branching, the formation of large clusters, the various layers 

 of tissue and the cell, finding that the internal structure of 

 the tubercle varies but little in relation to the various tissue 

 systems occurring in the normal root. The vascular cylinder 

 is surrounded by an abnormally developed parenchymatous 

 tissue which contains the parasite, and in Alnus serrulata, 



