1912] Knowlton,— Rare Plants in Groton, Mass. ` 235 
a station on the northern part of Manhattan Island. Britton’s 
Manual (1901) gives the plant and this station, adding “now nearly 
or quite obliterated” so this Groton station seems to be a new and 
separate introduction from Europe. The plant is in several charac- 
teristics quite different from Linaria vulgaris, and is not likely to be 
confused with it. The habit of the plant is different, as it has several 
slender branches and is less leafy, with wider leaves than its congener. 
The flowers are lemon yellow, the * butter" without much of the 
“eggs.” They, are smaller, with a conspicuous sharp-pointed spur 
7-10 mm. long. The capsules are 2.5-4 mm. in diameter, with slender 
pedicels 6-9 mm. in length. 
Prof. K. M. Wiegand has recently called my attention to a specimen 
of Amelanchier sanguinea (Pursh) DC. in my herbarium. This I 
collected May 13, 1905, on an esker in the eastern part of the town, 
where it grew near Epigaea and Hepatica triloba in the shade of white 
pines. This shrub is a pronounced calciphile, and has been found in 
calcareous regions in Maine, Vermont, and western Massachusetts, 
but this is the first report in this State from east of the Connecticut 
River, and from a region not definitely calcareous. 
Another shrub which often frequents limestone regions is abundant 
in the low land near Baddacook Pond close by, though very rare 
elsewhere in the county. This shrub is Potentilla fruticosa and was 
reported from this station by Dr. C. W. Swan in the Middlesex Flora 
(1888). 
Lappula virginiana is abundant in thickets along the roadside over 
a mile from the village, where it has every appearance of being part of 
the original flora. 
Another most interesting discovery this fall consisted of several 
medium-sized trees of Betula nigra. These grew on a gravelly knoll 
in a pasture between the village and the Groton School, fully two miles 
from the Nashua River. There was a straggling growth ‘of Betula 
populifolia and white pines with these trees. This station is so far 
from the regular home of the species along the Merrimac, and in such 
dry soil as to suggest that the trees have been introduced. ‘The tree 
is frequently set for ornament, but the pasture is too far from houses 
to make that likely in this case. 
HiNGHAM, MASSACHUSETTS. 
