FLOWERING PLANTS OF NANTUCKET 433 
and plain. This gives winter protection to the soil and in sum- 
-Mer a continuous shade and coolness under its low covering for 
such woodland plants as here and there may find space enough to 
make their growth. 
Nantucket has been called a treeless island and, apart from 
the town and the scattered farms, the casual tourist might be- 
lieve this to be true except for the naturalized pines which are 
now widely in the landscape. Nevertheless, twenty-five to thirty 
kinds of trees are native to the island, the larger reckoning allow- 
ing for those that, shrub-like on Nantucket, are trees in their full 
growth. In general, however, the Nantucket trees are not promi- 
nent in the vegetation, not many rising above a very moderate 
height, although there are copses and groupings in low grounds 
where they attain a good woodland size, and in the seclusion of 
dense thickets is to be found here and there a beech or an oak 
little noticeable for height but of a girth of trunk that reports a 
venerable age. Shrubs abound, and in swamps and low grounds 
are massed into thickets of the most dense and impenetrable 
character. The number of species that are botanically shrubs is 
seventy-two, many of them, however, bearing little distinction 
of aspect from the herbaceous vegetation amid which they grow. 
There are eight woody climbing vines and the same number of 
twining herbaceous species. Of other Nantucket plants having 
their particular habitats fifty-five belong to the salt marshes and 
twenty are of the coastal sands. Of thirty-three aquatics three 
only are exclusively maritime. 
The number of native families represented in the Nantucket 
flora is one hundred and thirteen. Thirty-eight have only one 
species, twenty-seven two or three species, twenty-six four to 
nine species and seventeen ten to twenty species. Only four 
families contain over twenty species, the Rosaceae with twenty- 
nine and the three predominant families, the Cyperaceae, Grami- 
neae and Compositae with eighty-seven, seventy-eight and 
seventy-two members. Including in the Rosaceae twenty-four 
hybrid blackberries that have been described (and other combina- 
tions among these occur) its actual membership would approach 
that of the three highly preponderant families. The ferns number 
twenty-six, belonging to three families, the Ophioglossaceae, five 
