Marshall—The Vegetation of Twin Island. 781 
■were great festoons of ground-nut (. Apios apios (L.) Mac M.) ; 
it extended, too, over the back strand and strand at this place 
■and was in full flower in August. A few small blackberries 
(Rubus baileyanus Britton) were found on the west side but 
not in flower or fruit. Here and on the south were two kinds 
•of roses ( Rosa humilis Marsh, and R. sayi Schwein) ; only one 
bloom was found. And lastly, to the south and west grew a 
thick and well defined border of poison ivy ( Rhus radicans L.) ; 
it never became large or vine-like, and only one cluster of berries 
was found. 
One small region deserves special mention. As has been 
already stated, the north bank rises rather abruptly from the 
strand to a height of nearly three meters, and here the .back 
strand and strand run together. The slope, the shade, and the 
abundance of water give the bank the appearance of the side of 
a miniature dell. On the top grew a single example of the red- 
berried elder ( Sambucus pubens Michx.) and the bristly goose¬ 
berry ( Ribes setosum Lindl.), the latter rare elsewhere. This 
was the only place where yarrow ( Achillea millefolium L.) was 
found in flower, and here was the only specimen of mullen 
( Verbascum thapsus L.), a small plant. On the rocks grew 
wild columbine ( Aquilegia canadensis L.) in full fruit. One 
tiny plant of maiden hair fern ( Adiantum pedatum ) was found 
here. And here also were a few small plants of the great 
water dock ( Rumex brittannica L.) which had apparently 
wandered in from the marsh where it grew luxuriously. 
Vernal plants were not abundant in the center; this would 
seem to be the result of the late season, made still later by the 
fact that the lake surrounding this small island freezes to a 
considerable depth in winter and keeps the spring temperature 
low. The more open low western end gave more species of 
early blooming plants; of these there were the wild spiknard 
( Vagnera racemosa (L.) Morong), the hairy Solomon’s seal 
( Solomonia biflora (Walt.) Britton), the sessile leaved bellwort 
( Uvutaria sessilifolia L.), a few plants of the false lily-of-the 
valley ( Unifolium canadense (Desf.) Greene), all in fruit, 
one kind of violet ( Viola renifolia A. Gray (?)’), one species of 
