38 BOTANICAL GAZETTE [JULY 
were perfectly colorless and without chlorophyll. 
The great difficulty of obtaining perfectly sterile cultures of 
moss protonemata upon an organic substratum will at once be 
evident to all who have ever worked in this line.. Goebel3° was. 
unable to obtain perfectly sterile cultures in his investigations 
upon Funaria hygrometrica. i perfectly sterile cultures could be 
obtained, it would be possible then to determine whether moss 
protonemata are able to thrive in the dark, when supplied with 
organic material, as sugar and peptone. This was the problem _ : 
which now presented itself for solution and to which my atten- 
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cent. solutions, the protonemata which were formed in the light | 
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tion was next directed. A considerable number of attempts 
were made, and at last my efforts met with success. The details 
of the experiments I will describe in the order in which they 
were carried out. 
The medium for the growth of the spores was made as fol- 
lows: 200° of 0.23 pro mille normal nutritive solution; 2 gf. 
grape sugar; I gr. peptone; I gr. agar-agar. The mixture was 
boiled on a water bath for three hours and then filtered, and 
preparations made in small Petri dishes. a 
Capsules of Funaria were selected which had the opercula 
still intact and attempts were made to sterilize them. They 
were first soaked in water until the water had penetrated them 
thoroughly and then placed in 1 per cent. formol for different 
lengths of time. The preparation of the cultures was carried 
out under all possible precautions against infection, in a chamber — 
which had been saturated with steam. So far as these experi- 
ments were concerned it was shown that an immersion in the 1 
per cent. formol for a length of time sufficient to kill the adher- 
ing germs, also proved fatal to the spores. 
In order to preserve the spores and at the same time have — 
the capsules in a sterile condition, I was obliged to resort to 
another method. The capsules were first dipped in melted 
paraffin and perfectly coated over, and then placed in the formol. 
The coating of paraffin thus prevented all penetration of the — 
3° GOEBEL, 
Sitzber math.-phys, Classe k. Bayer. Akad. Wiss. 26: 462. 1897: 
