1920] Wherry,—Soil Tests of Ericaceae and Other Families 39 
served in such material, but a few species elsewhere found in soils of 
low acidity were noted, such as Habenaria (Limnorchis) dilatata, 
Habenaria (Lysiella) obtusata and Castilleja pallida var. septentrion- 
alis. 
WILLOUGHBY LAKE, VERMONT 
The Willoughby Lake region is well known to botanists, especially 
from the excellent Flora published by Kennedy! in which previous 
work is summarized. Fernald? has discussed contrasts shown by the 
plants of this region and those of certain other localities in New Eng- 
land and adjacent Canada. The rock of Mts. Willoughby and Hor, 
Ordovician in age, is dominantly gneissic in character, with many 
calcareous strata, as well as granitic intrusions. The spring water 
seeping out from the faces of the cliffs has in practically every case 
traversed more or less limy material, and proved to be slightly alka- 
line in reaction; in rare instances it is neutral. The talus slope con- 
tains abundant calcareous rock fragments and its soils are mostly 
circumneutral in reaction. On the mountain slopes the soils vary 
in reaction, being cireumneutral where the calcareous strata outcrop, 
although there are also minor areas of acid soils over granite ledges, 
as well as in places where thick upland peat has developed. 
Few plants usually regarded as characteristic of acid soils are 
present in the Willoughby region. Colonies of Cornus canadensis 
occur on some of the acidic areas, and two acid-soil orchids, Habenaria 
(Coeloglossum) bracteata and Habenaria fimbriata (grandiflora) were 
noted in upland peat on the north slope of Mt. Willoughby. The 
only ericaceous plantsseen on the whole mountain were a few members 
of the Pyrola group: Chimaphila umbellata, Pyrola asarifolia, P. chlor- 
antha, P. elliptica, and P. secunda. All these grow in upland peat 
ranging from subacid to neutral in reaction. 
Of plants usually found in limestone regions, and presumably 
partial to alkaline soils, the following are noteworthy: Asplenium 
Ruta-muraria, Cryptogramma Stelleri, Woodsia glabella; Parnassia 
caroliniana, Saxifraga oppositifolia, S. Aizoon, S. aizoides, and Prim- 
ula mistassinica. Their soils were found to range from circumneutral 
to subalkaline. 
South of Willoughby Lake conditions are entirely different. Dur- 
ing the Glacial Period the ice advanced southward between Mts. 
! Kennedy, G. G. The Flora of Willoughby, Vermont. Ruopora, vi. 93 (1904). 
? Ruopora, ix, 149 (1907). 
