— 53 — 
The leaves on the stoloniform branches are very small as shown in Fig. 
3 in which such a leaf (d) is compared with a normal one. These small leaves 
are also veinless and have a more triangular form. The leaves are rela- 
tively far apart as shown in Fig. 2, in which c are paraphyllia. 
It is surmised that the branches serve as a means’of vegetative propa- 
gation, since they are easily shaken off in broken pieces, and were found in 
a very fine habitat for this species. The peculiar form is not a product of a 
peculiar season, since the old dead basal parts of the plants, certainly 
several years^>ld, show some of these stoloniform branches still attached. 
Eur hynchium stoloniferum grows attenuated when pendent and such forms 
have been described as Eur hynchium substoloniferum. Antitrichia curti- 
pendu la sometimes gets stoloniform when pendent ; but Neckera Menziesii 
being unusually pendent, could not have these branches due to the position. 
The great difference between the normal and the abnormal branches 
suggests at once a different function for the latter. If there is any physical 
reason for their formation it does not seem to be known. 
University of Washington, Seattle, Wash. 
SPORE DISPERSAL OF SPHAGNUM. 
The interesting observations of Mr. E. J. Winslow upon this subject in a 
previous number of The Bryologist (X:III. 1907) may be supplemented by a 
reference to Nawaschin Flora 83, 151, ff. with PI. IV. 1897 (not 1867 as 
Warnstorf gives it in Kryptogamenflora der Mark Brandenburg I, 313). 
Roth (Die europaischen Torfmoose, 1906) omits in his bibliography any 
mention of this very important article. The phenomenon of the explosive 
discharge of the spores of sphagnum has long been known to European 
bryologists. Nawaschin’s careful observations and experiments demonstrate 
the correctness of an hypothesis of Schimper that compressed air within th e 
capsule is the cause of the explosion. The air within the capsule occupying 
the place of the columella which is shrivelled up when the capsule reaches 
full maturity is compressed through a shrinking of the walls of the capsule 
caused by drying. This shrinkage affects only the transverse diameter of the 
capsule, the longitudinal one remaining constant. The normally globose 
capsule becomes then under the effect of dryness cylindrical, quite like a 
cartridge as Nawaschin puts it, the spores occupying the position of the shot? 
the compressed air that of the powder, the operculum corresponding to the 
outer wad, the membrane of the spore-sac to the inner one. The operculum 
is composed of a stiff and unyielding membrane and the result of the con- 
traction of the capsule-walls is eventually the bursting of the membrane 
connecting them with the operculum, thereby effecting the discharge of the 
cartridge. It should be added that the capsule-walls in sphagnum have 
only apparently functionless pseudo-stomata, so that the compressed air has 
no means of escape except the very slow one of diffusion through the tissues 
themselves. Nawaschin was able to compute the pressure of the compressed 
air in the dry capsule as equal to from three to five atmospheres. This 
sphagnal air-gun appears to be “ without a parallel among the mosses, if notin 
the whole vegetable kingdom.” A. LeRoy Andrews. 
Ithaca, N. Y. 
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