— 48 — 



munda to germinate in the dark ; but the temperature at 

 which the cultures were grown is unknown to me. A year 

 later, Schmidt, i with cultures of the spores of Aspidium vio- 

 lacens and felix-mas, confirmed the results previously ob- 

 tained by Borodin. In 1872 Kny 2 obtained results which 

 contradicted those of Göppert for Osmunda spores. The next 

 work of importance was that of Schelting 3 in 1875. He 

 worked with the spores of four different species and found 

 that in all cases germination occurred in the dark. One of 

 the species which he used , Aneimia Phylloides, was also 

 used by Borodin in the invettigations above cited. I have 

 not had access to the original paper, but the probability is 

 from the review, that the cultures were kept at a tem- 

 perature higher than the normal room-temperature. 



Again later , Gr. Beck 4 has shown that the spores of 

 Scolopendrium vulgare germinate only when exposed to light. 

 ' Milde 5 and Sadebeck" have shown that the spores of 

 Equisetum germinate in the dark as well as in the light, 

 while Leitgeb 7 in his excellent work on the liverworts has 

 shown that darkness prevents the germination of the spores ; 

 also that faint illumination causes the development of proto- 

 nema which differ markedly in form from those grown under 

 normal illumination. With this short historical summary as 

 an introduction I will proceed to the results of my own in- 

 vestigations. 



3. EXPERIMENTAL. 



The same method was used as has been previously described 

 for the experiments with moss leaves: either filter paper in 

 Petri-dishes, or pieces of flowerpots, or sterilized earth. Any 



1 1. c. p. 20. 



2 Jahrb. f. wiss. Bot. 8 : 4. 1872. 



3 Bot. Jahresber. 1875, 328. 



4 Bot. Zeitung, 36 : 780. 1878. 



5 Nova Acta Acad. L. C. F. 23 : 2. 



6 Bot. Zeitung, 35 : 44 and 45. 1877. 



7 Sitzungsber. d. Akad. d. Wiss. Wien. 74 : 1. 1876. 



