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The medium for tlie growth of the spores was made as 

 follows: — 200 cc of */ 4 P ro mille normal nutritive Solution. 

 2 gr. — grape sugar, 

 1 gr. — peptone, 

 1 gr.— agar-agar. 



The mixture was boiled on a water bath for three hours 

 and then filtered, and preparations made in small Petri-dishes. 



Capsules of Funaria were selected which had the oper- 

 cula still in tact and attempts were made to sterilize them. 

 They were first soaked in water uhtil the water had pene- 

 trated them thoroughly and then placed in l°/ formol for 

 different lengths of time. The preparation of the cultures 

 was carried out under all possible precautions against in- 

 fection, in a Chamber which had been saturated witll steam. 

 As far as these experiments were concerned it was shown 

 that an immersion in the l°/ formol for a length of time 

 sufficient to kill the adhering 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 parafin and perfectly coated over, and then placed in 

 the formol. The coating of parafin thus prevented all pene- 

 tration of the formol into the inferior of the capsules. Then, 

 by operating in the Chamber which had been saturated with 

 steam, perfectly sterile cultures were prepaired. 



The Petri-dish cultures offered subsequent opportunties 

 for the penetration of moulds, even when extreme care was 

 taken, so that cultures which had been kept sterile for sev- 

 eral weeks would often be spoiled by the inroads of fungi. 

 The best results were obtained with cultures made in 

 Erlenmeyer flasks. 



Cultures of Funaria protonema were kept in Erlenmeyer 

 flasks from the first of Jan. to the Ist of May, four months, 

 in perfectly sterile conditions, and in both light and darkness. 

 Parallel with these was a culture started at the same time 

 upon sterilized earth. The mode of growth of the protonema 



