512 BOTANICAL GAZETTE [JUNE 
basi decurrentibus membranaceis utrinque arachnoideo-tomentulosis 
plus minusve glabratis, petiolis alatis, foliis superioribus sessilibus 
lanceolatis irregulariter dentatis; pedunculis elongatis usque ad 8 cm. 
longis unicapitatis; capitulis 1.8-2 cm. altis multifloris radiatis sub- 
nutantibus; involucris campanulatis calyculatis; squamis involucri 
lineari-lanceolatis 13-15 mm. longis apice acutis penicillatis extrinsecus 
arachnoideo-tomentulosis; floribus femineis 12-15, ligulis lanceolato- 
‘ oblongis 12-15 mm. longis 3-4 mm. latis flavis; floribus disci numerosis, 
corollis ca. 8.5 mm. longis; pappi setis albidis subaequantibus; achaeniis 
glabris. 
On talus slopes of Mt. Angeles, Clallam County, Washington, altitude 
about 2000 m., 2 September, 1909, E. B. Webster, no. 109 (hb. Field Museum 
cat. no. 251971). 
In habit S. Websteri is similar to S. seridophyllus Greene which, however, 
is glabrous throughout and has smaller heads and shorter rays. In foliar 
characters S. Websteri resembles S. Elmeri Piper, but differs in having much 
larger and solitary heads. Mr. E. B. WessTer of Port Angeles, by whom the 
specimens were collected, in commenting on the plant, states: “There are 
possibly a hundred plants in all, a few growing at the northern side of the base 
of one of the pinnacles, the remainder being scattered along the narrow rocky 
talus for possibly 1000 ft.; on the slope at the base of the pinnacle Arnica 
cordifolia Hook. and Heuchera racemosa Wats., both rare on Mt. Angeles, were 
associated with the Senecio, and somewhat lower down Hedysarum occidentale 
Greene and Arabis Lyallii Wats. were growing along with it.”— 
GREENMAN, Chicago 
SOIL MOISTURE IN THE COTTONWOOD DUNE ASSOCIATION 
OF LAKE MICHIGAN 
(WITH ONE FIGURE) 
The following data regarding the range of soil moisture in the cotton- 
wood dune association upon the shores of Lake Michigan seem to be of 
sufficient interest to warrant their publication in advance of the results 
of moré extensive studies of the same sort now in progress. The work 
of CowLEs' upon its general ecological relations and that of the writer? 
upon the evaporating power of the air have shown this to be an open 
association of a single tree species, together with a scanty undergrowth 
t CowLes, H. C., The ecological relations of the vegetation of the sand dunes of 
Lake Michigan. Bor. Gaz. 27:95-391. at 
2 Futter, G. D., Evaporation and pl i Bot. GAz.522193-208. IgIt. 
