— 49 — 
aquatic specimens an occasional tendency to have its branch-leaves serrulate, 
the teeth being due solely to a slight extension of the distal ends of the narrow 
border cells. This might readily be regarded as a casual variation having no 
taxonomic value, but it is significant that it does not occur in other species, 16 that 
it is not characteristic of all aquatic specimens of S. cuspidatum, and that in 
some regions this form becomes more frequent or even supplants the normal 
form entirely. Warnstorf in 19 11 leaves two North American species of this 
category, S. serratum Austin, 1877 (including the European form), and S. tr ini- 
tense Carl Muller, 1848, 17 but without any very definite characters to distinguish 
them from each other. 18 With us the plant is confined to our east coast, the 
most northerly station being in Maine. 19 It is also known from Massachusetts 
and becomes common in the southern coastal states, reaching to Louisiana. 
It further occurs in Bermuda, where it is the only Sphagnum except S. magel- 
lanicum, and in Porto Rico (where it has acquired another synonym, S. Helleri 
Warnstorf, 1905), extending through Trinidad apparently to eastern South 
America. Warnstorf includes specimens from Japan and Australia, while sev- 
eral of his other species from the southern hemisphere are possibly identical. 
It is sometimes found richly fruiting, as is normal S. cuspidatum in spite of its 
dioicous inflorescence. The close relationship of S. Fitzgeraldi Renauld will be 
discussed under the latter species. 
To revert to a species previously discussed, a new locality for 5 . Angstromii 
has come to light in good specimens from Nome, Alaska, collected in 1918 by 
C. W. Thornton, which I have been able to examine through the kindness of 
Mr. Maxon. This is the second station for this subarctic species from the Amer- 
ican mainland, the third from North America altogether. Further collecting 
may show it to be not uncommon in northern Alaska, the Yukon and possibly 
farther eastward. It is however strange that it has never been reported from 
Greenland, whose Sphagnum-flora is so well known that one hesitates to believe 
it can occur there without having been discovered. If it should not in future 
be found there nor in the adjacent eastern parts of arctic or subarctic America, 
the conclusion would seem inevitable that it had reached Alaska in its distribu- 
tion from Asia and had not yet succeeded in spreading across arctic or subarctic 
America to Greenland. 
Ithaca, N. Y. 
1G Except S. Fitzgeraldi, exotic species having this character are synonyms or closely related. 
17 Separated by nearly 30 pages of print. The author in his Vorwort congratulates himself 
on the natural arrangement of species in his keys and descriptions. 
18 He puts one of Mrs. Britton’s numbers from Pembroke Marsh in the Bermudas under 
one of the two species and her other number from the same marsh under the other. 
19 A specimen in the Austin herbarium labeled “from a pit in a peat swamp wholly submerged, 
Hebron, Maine, Aug., 1878” has a note by Austin calling attention to the serrulate leaves. Mr. 
G. K. Merrill has recently sent me an entirely similar specimen from a “pool in a bog, Union, 
Maine, Aug. 17, 1919. 
