FLOWERING PLANTS OF NANTUCKET 367 
appearing cat-tails that seem to call for critical study. One is 
the abundant species of our coastwise marshes, the other a scarcer 
and much more slender and narrower-leaved plant perhaps exclu- 
sively of fresh water bogs. A comparison of living plants, in 
July, 1912, showed a very obvious difference in their general color- 
ing, the narrower-leaved plant quite wanting the bluish tinge of 
leaf and stem so characteristic of the other; the leaves were also 
more attenuate, and considerably longer at the time the plants 
were beginning to bloom, and the very slender spikes were sepa- 
rated by an unusually wide interval. Less obvious differences 
were the more striate stem of the smaller plant and the absence 
from its cortex of the numerous pale puncticulae that, under a 
lens, appeared distinctly in the contrasted form. On July 1 
the slender plant was just in flower, the broader-leaved form some- 
what more advanced. Typha latifolia was not seen in flower until 
July ro. 
Sparganium eurycarpum Engelm. Much earlier flowering than 
the other island species; fruiting heads are of full size sometimes 
as early as the third week in June. S. americanum had no mature 
staminate flowers up to July 12, 1912. 
Potamogeton Oakesianus Robbins. Flowering and fruiting 
abundantly in June. 
Potamogeton pulcher Tuckerm. Flowering abundantly, some- 
times before the end of May. As early as June 5, IQII, it was 
blooming freely and bore well-formed fruit, while yet the leaves 
were far from maturity, even the uppermost retaining their early 
tenderness and pinkish-brown color. 
Potamogeton pectinatus L. In full flower and with immature 
fruit as early as June 10, 1908. 
Ruppia maritima L. Professors Fernald and Wiegand, in 
their paper, “The genus Ruppia in eastern North America” 
(Rhodora 16: 119-127. pl. ro. 1914), have referred the Nantucket 
plant to var. longipes Hagstrém, citing and figuring a specimen 
collected in Sachacha Pond by Professor F.S. Collins. Specimens 
of this form collected in Sachacha Pond, June 12, 1911, were in 
full flower. It is quite possible that plants observed in a ditch on 
