— 41 — 
Exsic. no. 261, Plate IV. Fig. 6. was also sent me from Mount Washington 
by G. K. Merrill. This form is little known even in Europe, and is not 
regarded worthy of varietal rank, Tuckerman doubtless knew of it, for he 
speaks of the squamules sometimes occurring in the present variety. We 
figure the form laontera as well as the usual expression of the variety. The 
variety is known in all the grand divisions except Australia, commonly in 
mountains. 
The various forms of Cladonia gracilis commonly occur on earth, on 
horizontal rocks covered with a small amount of humus, or on rotting wood. 
The plants are usually found in forests, preferring shade, and are often 
among mosses. The last variety descends to the tundras in northern regions 
and there often occurs in sunny and windy places. Grinnell, Iowa. 
PHAENOLOQICAL OBSERVATIONS ON MOSSES. 
H. Wilhelm Arnell. 
In the Bryologist there appeared, in the year 1904, p. 35-36, a note on 
“The Fruiting Season of the Hair-cap Moss,” by Phebe M. Towle and Anna 
E. Gilbert, that interested me much as it touched upon a subject which I 
myself have studied. A rather long time ago I studied the seasons of bloom- 
ing and fruiting of the Scandinavian mosses (musci veri). The results 
of my researches were summed up in a paper, “ De Scandinaviska Lofmos- 
sornas Kalendarium (Upsala Universitets Arsbkrift, 1875) in which the sea- 
sons of blooming and fruiting of all Scandinavian mosses known at that 
time were indicated as accurately as the material that was accessible per- 
mitted me to solve these questions. Since that time there has, as far as I 
know, nothing been published on the phaenological relations of the mosses 
till the paper of A. Grimme, “ Ueber die Bliithezeit Deutscher Laubmoose 
und die Entwickelung ihrer Sporogone “ appeared in Hedwigia, 1903. 
I will now tell the results to which I have come with regard to the Hair- 
cap mosses. The species of Polytrichum, I found phaenologically to consti- 
tute two different groups. The species belonging to Ymnitrichum (Neck ) 
Lindb., namely P. urnigerum , P. nanui 7 i and P . subrotundum , bloom at an 
early season at Upsala, in May or the first week of June, and the lids of the 
sporogones are therefore cast in the winter or early spring, at Upsala in 
December to April. These mosses thus require less than a year or seven to 
ten months for the development of thfeir sporophytes. The majority of the 
Scandinavian Polytricha, the sections Pterygodon Lindb. and Euleiodon 
Lindb., bloom early in the summer, at Upsala in June and July, while the 
sporogones become ripe in July or the first days of August. These species 
require more than a year or about thirteen months for the development of 
thek fruits. The two species of Polytrichum, P .juniperinum and P. commune, 
observed by the Misses Towle and Gilbert, both belong to the latter group 
of Hair-cap mosses. A comparison of their dates with mine shows a rather 
great difference, as according to the observations in Vermont, these mosses 
bloom in April, and the maturing of the spores takes place in August of the 
