— 55 — 
Professor Hotson ( l c .) regards S. imbricatum as the most desirable species for 
surgical work, with S. palustre second, and S. papillosum third. In the east 
the order of excellence appears to be exactly reversed, S. papillosum being re- 
garded as by far the best species (see Porter, l c.). Further, the sphagnums 
attain their optimum growth in bogs, and, when present, the best qualities of 
surgical sphagnum almost invariably frequent the wettest parts of a bog. This 
is true even in the humid northeast, but it is even more so in regions where cli- 
matic conditions are less congenial. The same species (e. g. S. papillosum) 
may grow throughout a bog, yet it may attain the requisite degree of luxuriance 
only in the wettest, quakiest parts of the bog; elsewhere, not only will it be poor 
in quality, but the chances are that it will be more or less intimately mixed with 
undesirable species. In searching for surgical sphagnum, it is a good rule to avoid 
wooded swamps, for while sphagnums usually are present in abundance in such 
places, for various reasons the material generally is of too poor quality to be of 
surgical value. Bogs which are densely popula ted by heaths or other bushy growth 
likewise furnish unfavorable conditions, except locally, where there are wet, open 
depressions. The same may be said of bogs that are densely overgrown with sedges 
or grasses so much so as to give them the aspect of a meadow. S. papillosum 
in particular, requires plenty of sunlight as well as plenty of water. In bogs 
which have been flooded, as frequently happens through the damming of a 
lake, the better grades of sphagnum have usually been drowned out. S. papil- 
losum seems especially sensitive to any change of environment. Along the 
coast in eastern Maine, the lumberman has thus been responsible for the exter- 
mination of much of the surgical sphagnum which formerly occupied the “flow- 
age” swamps bordering many of the lakes and streams. During a recent trip 
of investigation in this region, the most ideal conditions for S. papillosum were 
found to be in low, wet, quaky bogs along the borders of well-drained ponds or 
small lakes, and in similar situations along slow streams. In favorable situations 
of this sort, this moss may comprise the bulk of the vegetation, building up 
broad cushions, often a foot high, and forming a more or less continuous ground 
cover. From a distance the most conspicuous plants in such an area are the 
“cranberry grasses” {Car ex filiformis, C. oligosperma ), which, on closer inspec- 
tion, are usually found to form a rather scanty, open growth. Cranberries 
{Vaccinium macrocarpon ) are practically always present, together with a scatter- 
ing of low shrubs, such as sweet gale {Myrica Gale) and various heaths. Con- 
sidered from the standpoint of the ecologist, it can be said that not only are 
bogs which have arisen through the intervention of a floating mat most favorable 
to surgical sphagnum, but 5. papillosum in particular is far more likely to flourish 
in a bog where the mat-forming pioneers are sedges than in one where the pioneers 
are shrubs. 
Taken as a group, the sphagnums are much more widely distributed in 
cool, humid regions than in warm, relatively dry regions. From a climatic 
point of view, the most favorable regions in the east are eastern Maine and the 
country lying to the northeast, along the coast: the region in which raised bogs 
are encountered. The best eastern material thus far collected in quantity came 
