Physiological Stuilies on Schistostega osmundacea. 23 



I then poured in eacli dish a different kind of nutritive solution, 

 and planting the moss on the sand, examined its growth in each 

 dish. The kinds of nutritive solution used were : — 



a) Solution of Elte and Emile Makchal/^ 



h) Pfeffer's solution. 



c) Detmer's solution. 



d) Knop's solution. 



On the 10th of !March I put the above-mentioned Petri 

 dishes, each in a wooden box as described on page 10. On the 

 15th of May, I observed that the development of tlie moss in the 

 dish containing the Marchal solution was the best, the protonema 

 producing a large number of shoots and spreading over the whole 

 surface of the sand. In the dishes containing the Knop and 

 Detmer solutions the growth of the moss was not so good, the 

 protonema producing fewer shoots and growing over only half its 

 surface. In the dish with the Pfeffer solution the growth of the 

 moss was observed to be the worst. In all these cases, however, 

 the plant was seen to be thriving, showing that each solution 

 contained more or less the kind of nourishment it required. Again 

 I poured the four different kinds of nutritive solution each on a 

 small quantity of soil taken from the place where the moss had 

 been growing, and found, as I had expected, that the moss throve 

 best on the soil nourished with the Marchal solution. 



Liquid culture. — I put the moss into four Erlenmeyer bottles 

 of 100 c.c, with 20 c.c. of the four kinds of solution respectively! 

 From 7 to 10 days later, many adventive protonemata wore seen 

 on the various parts of tlie stem. The shoots floating on the 

 surface of the liquid had produced, down in the liquid, adven- 



1) This solution should be neutralized before use. 



