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• 

 In the cultures wlrich had been kept at 29° and 32° C germination 



was retarded for a few days, but the the spores from the 



remainder of the cultures grew after the usual length of 



time. 



The length of time required for germination, and the 

 condition of the material rendered the preparation of sterile 

 cultures impossible, so that the cultures with grape sugar 

 were not very satisfactory. Although I did not succeed in 

 bringing the spores to germinate under these conditions, they 

 gave every indication of growth , and I attribute the failure 

 to germinate only to the inroads of bacteria. In the dark in 

 sugar Solution , the spores increased to 3 or 4 times their 

 original diameter and formed large starch masses the some 

 as in the moss protonema. 



Further than this they could not be brought, although 

 repeated attempts were made , and when the cultures were 

 placed in the light, even then germination did not proceed, 

 showing that the spores had not remained capable of germination. 

 If however the cultures could have been kept sterile, there 

 was every indication that the spores would have germinated. 



c. FERN SPORES. 



A culture of the spores of Cerathopteris thalictroides was 

 kept in the dark for three months without any signs of 

 germination, while a sowing of the same spores germinated 

 in the light after twelve days. Experiments with the spores 

 Alcophila Loddigesii led to the same results. Thus for the 

 species investigated, it can be stated as certain, that under 

 ordinary conditions of nourishment and at a temperature of 

 19 — 21° C. the spores are not capable of germinating. The 

 effect of a higher temperature was then tried for the spores 

 of Cerathopteris, a culture of the spores being kept at 32° C 

 in the dark. After a lapse of sixteen days the culture was 

 examined and it was found that the spores had germinated 

 abundantly. The form of growth was that of a cell iilament, 

 seven or eight cells long, the whole being about 2 mm in 

 length. The basal cell always produced a rhizoid, and in 



