PHYSIOLOGY AND MORPHOLOGY OF CALIFORNIA HEPATICZ 27 
So long as the water of constitution is not disturbed the de- 
gree of desiccation seems to make no perceptible change in the 
reviving powers of all our common xerophytic forms. In the 
preparation of a previous paper’ quantitative experiments were 
made upon Fossombronza longiseta to ascertain the actual water 
content of air-dried plants and to test the vitality of plants and 
spores that had been for several weeks subjected to the action 
of such a powerful drying reagent as glacial phosphoric acid. 
The results obtained showed that the plants of this species in 
the normal air-dry condition contain an appreciative amount of 
water which may be removed without the slightest injury to the 
vitality of the plant, while spores subjected to the same treat- 
ment germinate quite as readily as those under perfectly normal 
conditions. ‘To extend these results the same experiment was 
carried out with Zargzonza hypophylla, Kimbriaria californica, 
feiccia glauca, Porella bolandert, Cryptomitrium tenerum and 
again with Fossombronza longiseta. All material was collected 
early in September before the first rains, was brought into the 
laboratory where, with a fine stiff brush and other instruments, 
it was carefully freed from any soil particles that might be 
clinging to the rhizoids. ‘Then to correct an error that might 
creep in from the absorption of moisture by the plants from the 
fingers or breath of the operator the plants were again subjected 
to normal air-dry conditions a number of days. 
Following this the five lots of each plant, were carefully 
weighed on a chemical balance and then placed at once in the 
recelving chamber of a desiccator over a quantity of glacial 
phosphoric acid. Here the material was left from September 
21, 1906, until February 9, 1907, when it was again weighed 
and the respective weight losses recorded. ‘The weights before 
and after artificial drying are given below: 
Normal Air-dry Loss of Weight After Four 
Fimbriaria. Weight. Months Desiccation. 
lot I 0.05 g. 0.0025 g. 
lot 2 0.05 g. 0.0007 g. 
lot 3 thrown out as defective. 
lot 4 0.072 g. O.009I g. 
lot 5 0.105 g. 0.0047 g. 
4Toc. cit. 
