Great Basin: Mohave Distriet. 587 
Between timber line and this pine belt is a belt characterized by Pinus 
flexilis and P. arıstata. In none of these desert mountains does a true timber 
line exist, but northward the White Mountains of Nevada and southward the 
San Bernardino Mountains extend above this limit. According to COVILLE 
an abnormal condition of affairs exists on the Panamint where owing to the 
absence of P. fonderosa var. scopulorum, which reaches its western limit in 
the Charlestown Mountains, P. monophylla grows to an unusually high altitude 
and P. flexilis and /. aristata unusually low, so that the bull pine belt appears 
to be crowded out entirely, although still marked by the presence of Juniperus 
oceidentalis and Cercocarpus ledifolius. 
Chapter IV. North American Temperate Zone: Pacific Section. 
1. Sitkan Region. 
This region extends from Cook Inlet south to the fifty-first degree of 
north latitude (the northern limit of Pseudotsuga Douglasii), west of the conti- 
nental divide and includes coastal Alaska and British Columbia with the more 
northern portion of Vancouver Island. In its northern extension, far to the 
subarctic territory along the southern tributaries of the Yukon River, it mingles 
with the flora of the glaciers, the arctic plant associations and the timber 
boundary of the northern coniferous forest the western pacific floral element 
has a very interesting complexity, as shown by the illustration of the Davidson 
Glacier (plate XIV.) It is a region characterized by deep fiords like Norway, 
but with a far richer forestation. Fogs and heavy rains are frequent and the 
snow line on the unbroken chain of coastal mountains is at 2,500 and 3,000 feet 
and numerous large glaciers descend from the snow fields to the shore. The 
coast is fringed by hundreds of forest-clad islands which form an inland pas- 
sage from Vancouver Island north to 59° N. lat. 
ı. Halophytic Formations. 
Marine Algal Formation. The algae of the Pacific coast north of . 
Sound extending northward to and including those of Bering Sea and whic 
Characterize that region are Odonthalia aleutica, Polysiphonia bipinnata, E ulhore 
cristata, Rhodymenia pertusa, Constantinea rosamarina, Fucus ee 
Megacephalus, Agarum Turneri, Cymathere triplicata, Lammarta ER n. 
L. bullata, Dictyosiphon foeniculaceus and Myelophycus intestinalis') : 
Shelves of marine vegetation may be distinguished on the Alaskan coast. 
Sublittoral Shelf. The marine algae of this shelf are: Cost 
sima (on rocks), Iridaea membranacea, Gigartina pacifiea (on rocks), 
Euthora cristata (abundant), Rhodymenia pertusa (on rocks), Rhodyme 
I 
aria Turneri, Porphyra amplis- 
Ahnfeldtia plicata (on rocks), 
nia palmata (on rocks), 
r “tion, Vol. V. Crypto- 
r) SAUNDERS, DE ALTON: See Bibl. p. 55, and: Harriman Alaska Expedition, 
gamie Botany, 1904: "s5—2ır, 
