86 
Humphrey .— The Development of 
In preparing plants for the fixing solution it was noticed that in some 
cases the stem was more or less thickened, taking on something in the 
nature of a tuberous growth as shown in Text-Fig. 3. A more detailed 
examination of the contents of this stem-enlargement revealed the presence 
of fungal hyphae, and in every case 
these were always present. In fact, 
on close scrutiny, it is found that few 
plants escape infection. Just what 
is the true relation between the host 
and the fungus cannot be said, but 
in a later paper an attempt will be 
made to throw some light on the 
problem. 
It is barely possible that the tuberous thickening of F. longiseta , at 
least as it occurs here is a pathological structure, functioning physiologically, 
however, as a storage organ. 
No amount of desiccation seems in any way materially to affect the 
ability of Fossombronia to revive, or to influence its rate of growth. Material 
brought into the laboratory during the dry season was subjected for several 
days to the action of a powerful drying reagent, in this case glacial 
phosphoric acid. The material was collected in the latter part of September, 
from an exposed and thoroughly dry roadside embankment. In the air- 
dry condition the plants weighed -107 gr. ; after treatment with glacial 
phosphoric acid till no further loss of weight was perceptible, they were 
observed to weigh *IC2 gr., or *005 gr. had been given up by the material, 
or 4*6 per cent, of its air-dry weight represents the actual water-content of 
the plants before subjection to the drying reagent. Upon removal from 
the bottle containing the glacial phosphoric acid, they were at once placed 
in a Petri dish upon damp earth and covered. After twenty-four to forty 
hours the plants were as green, and as far advanced as those not artificially 
dried, and within twelve days many spores had germinated that had clung 
to the material during the experiment. This test has not been applied to 
the other Archegoniates common to this region of long dry summers, but 
as stated by Campbell 1 they no doubt possess a degree of adaptation quite 
as pronounced as that seen in Fossombronia. 
Experiments by Peirce 2 upon the behaviour of Lichens in this region 
go to show that the influence of our summer morning fogs is considerable, 
and it is not improbable that the Hepaticae are more or less affected, to 
such an extent, in fact, as to cause a slight growth. 
The development of tubers or tuber-like thickening of the stem among 
Liverworts is not uncommon. Goebel 3 has described and figured a species 
1 Campbell (’04), p. 86. 2 Peirce (’99). 3 Goebel (’98), Teil ii, Iiefl 1 . 
Fig. 3. An example of tubercular thickening 
of stem. X 1 12. 
