14 BULLETIN 1053, U. S. DEPARTMENT OF AGRICULTURE. 



case the reduction in the percentage of germination was only from 

 48 to 37 per cent. In others, it was from 70 to 20 or 30 per cent. In 

 most of the tests, however, the reduction was more pronounced, re- 

 sulting in no germination or only 2 to 5 per cent. The lack of uni- 

 formity in results is probably to be explained by differences in the 

 condition of the spores, length of time they remained wet, and time 

 taken to dry. 



It was found in the preliminary experiments of the effect of 

 light upon germination that spore prints left out of doors over night, 

 even though protected from falling water, lost their viability after 

 one or two nights and days. Similar spores retained their normal 

 viability, however, when protected over night in a closed desiccator 

 (without drying chemical). Spores of all five fungi studies behaved 

 in the same manner. The explanation is probably to be found an 

 the diurnal changes of atmospheric humidity. 



OBSERVATIONS ON THE CASTING OF THE BASIDIOSPORES. 



Buller (5, p. Ill) has shown that fruit bodies of Lenzites sepiaria 

 can be revived and made to cast spores after four months of drying. 

 Falck (IS, p. 66) revived them after one year and nine months of 

 drying. The writer collected some sporophores of this plant from 

 prostrate white pine in Wisconsin in June, 1919. The weather had 

 been sufficiently moist to allow the formation of an abundance of 

 sporophores and it is not known how long any of them had been 

 casting spores. The collections were taken inside and left for a day. 

 They were then moistened over night and placed upon glass slides 

 the next day for spore casting. At night the prints were collected 

 and the sporophores allowed to dry on a table in the room until the 

 night of the second day following, when they were again moistened 

 for another cast the next day. With this rotation of 48 hours of 

 drying in the room, 12 hours of wetting, and then 12 hours of cast- 

 ing, spore prints were obtained six times. The seventh time the 

 sporophores failed to produce visible prints. 'Several sporophores 

 collected when frozen in November, 1919, and then kept in an ice 

 box for one month were treated in a similar manner in the labora- 

 tory. Visible casts were obtained four or five times from single 

 sporophores, even through the summer of 1920. 



Sporophores of Lenzites sepiaria kept in the laboratory were re- 

 vived after 15 months and usable prints obtained, but the same ones 

 would not revive after two years. Sporophores which had over- 

 wintered out of doors during 1919-20 (one set in Providence, R. I., 

 and the other in northern Vermont) were made to cast spores in 

 early March and April, 1920. « 



Sporophores of Lenzites trdbea have been revived after six to nine 

 months, but repeated castings have not been obtained from the same 



