Maritime Distriet: Mt. Washington. 375 
Picea nigra in mixture. This type of forest rarely extends above an altitude 
of 2,400 feet (732 m). The ground cover consists of Viburnum lantanoides 
(= V. alnifolium), Acer pennsylvanicum and Sorbus americana. 
ipine Formations. The timber line on Mount Washington averages 
4,000 feet (1220 m). The dwarf timber (Krummholz, pucker bush, Dwarf Tree 
Formation) is clearly demarcated but not so extensive as on Mount Katahdin‘). 
Picea nigra gradually degenerates until it becomes flat-topped and closely 
matted together while in the ravines above tree limit are dense thickets of 
Alnus viridis. The summit of Mount Washington is bare in the extreme and 
characterized by angular boulders of granite covered with lichens: Auellia 
geographica, Umbilicariae, Cetrariae, Cladoniae. Enormous ravines seam the 
sides of the mountain designated as Great Gulf, Tuckermans Ravine, Hunting- 
don Ravine. These ravines support a variety of rare and local mountain and 
alpine on 
ne Canyon Formation. In Tuckermans Ravine above the snow arch the writer 
collected a ea ser au um supinum, Phleum alpinum, Castilleja pallida, Veronica 
alpina, nica chamissonis, naria dilatata, Viola palustris, Streptopus amplexifolius, and 
A]: or A in aadikior ee viridis (= A. alnobetula, A. crispa), Oxyria digyna, Salix 
ie Sibbaldia procumbens, Loiseleuria re Epilobinm alpinum and Geum radia- 
(= G. Peckii), while Heracleum lanatum, Veratrum viride, Houstonia coerulea, Cornus cana- 
ai Linnaea borealis have ascended from the ihre to mix with the alpine species. The 
presence of the rare Viburnum pauciflorum, Baeomyces placaphylius in this ravine is noteworthy, 
ile the fungus Se epilobii is found nowhere else in the world. Oxyria digyna, an 
hypnoides, an ee (= Phyllodoce caerulea), Castilleja pallida, Geum radiatum, Dia- 
pensia lapponica, Veronica alpina, Stellaria borealis, Epilobium anagallidifolium, Luzula a 
. Spicata, Ba illa a tata, Juncus triidus, Salıx her nee alix res nn 
selago, Coptis trifolia were noticed by me at the head of the t Gulf where Oxyria digyna, 
Saxifraga rivularis with Cardamine bellidifolia form an et in ee me rivulets os ria- 
Association). The other plants form an association of varying character according to the 
predominance of ed one or two species occurring on the shelves of the steep declivities of 
this ravine, (Cassiope-Bryanthus-Diapensia Association). The mosses of the great 
ulf rim are Dieanım fulvellum growing in the crevices of moist cliffis; Conostomum boreale 
also occurs, while on wet banks of rivulets are Rhacomitrium fasciculare, en squarrosum, 
Gymnocybe turgida, Er fluitans, H. dilatatum, H. stramineum. 
The summit plants divide themselves into two groups those found amid the 
boulders and on the steeper slopes and those found on the plateau known 
as the Alpine Garden. 
The Alpine Garden according to my observations is a level table-land slightly inclined down- 
ward some distance below the summit. The ‚plants are characterized by their short stature 
(nanism) scattered over the surface with pebbly, Ba ae or clayey soil between the plants 
and an abundance of lichens and mosses. The flow plants mostly assume the cusbion form 
aud have a multicipital ag root, or rhizome ie F er ER 2). On the prot- 
ected upper edge of the garden which is practically alpine in its meteorologie and physiographic 
features occur stunted ups of Picea nigra (= P. mariana) which are closely matted together 
1) Cf. Suaw, C. H.: Causes of Timber-line on high Mountains. The Plant World XII: 169. 
2) WArMInG, Euc. and VaHL, M.: Oecology of Plants; an Introduction to the Study of Plant 
Communities 1909: 256—261. : 
