438 BICKNELL: FERNS AND 
If we may picture this region in the formative period of its 
present flora as enriched with a vegetation crowded along the 
shore lines of bays and inlets from sound and sea, just as today in 
such situations plants have assembling places that delight the 
botanist, then today’s surprises in this inward coastal flora have 
their explanation. For Nantucket, then perhaps little more than 
a headland flanked with bleak sand wastes along an exposed outer 
coast, must have proved a difficult and impermanent refuge to 
many southern species that would find encouragement and per- 
petuation along the quiet inward shore lines further to the north. 
Fragmentary and unclear as these seeming evidences may be 
they unite in suggesting a closer affinity in Nantucket’s flora with 
the flora of a more eastern region than with that of the northward 
mainland more nearly at hand. And if there be revealed in this 
the broken ties of an ancient relationship it traces itself con- 
formably with the general trend of the coast and with that diagonal 
northeastward-southwestward sweep of distribution that has 
given their geographic lines to so many of our plants in their 
eastern range. 
The following northward species of Nantucket are unknown 
in the coastal region of New Jersey, not many of them passing on 
even to Long Island. 
Phegopteris Phegopteris Myrica Gale 
Isoétes Tuckermani Corylus rostrata 
Panicularia grandis Persicaria Hartwrightii 
Scirpus occidentalis Tissa canadensis 
‘““ rubrotinctus Coptis trifolia 
“ pedicellatus Ribes oxyacanthoides var. calct- 
Eriophorum viride-carinatum cola 
es utriculata Fragaria terrae-novae 
Goodenovii Argentina litoralis 
‘*  monile Rubus strigosus 
‘“  subloliacea “  triflorus 
“ prairea Lathyrus pilosus 
“  diandra Ilex bronxensis 
Lemna trisulca oe palustre 
Juncus balticus lineare 
*“*  bufonius var. halophilus xe strictum © 

