Northward extension 
Magnolia glauca eg M. virginiana). 
Hudsonia ericoid 
Ascyrum these (= A. bypericoides). 
Arenaria en (= 
Polygala 
Rx a virginiana. 
Desmodium (Meibomia) laevigatum. 
A. caroliniana). 
Desmodium (Meibomia) viridiflorum. 
Rubus cuneifolius. 
Crataegus uniflora (= C. parvifolia). 
Eupatorium tofand)tolieiN: 
Aster nemorali 
Aster Fe 
Eee mariana. 
of Atlantic Areas. 
219 
Kalmia angustifolia. 
Ipomoea 
ie) 
» 
Asclepias obtusifolia. 
Euphorbia ipecacuanh 
Quercus marylandica (a nigra). 
Q. prinoides. 
Q. phellos 
et heeerie simplex. 
Juncus es var. macrostemon. 
Xyris Alan 
Cyperus rege 
Stipa ave 
Glyceria asien obtusa. 
Panicum verrucosum. 
Andropogon er atus (= macrourus). 
Lycopodium inundatum var. Bigelovii. 
n m purpureum. 
OHR dumosa. 
Andromeda (Pieris) mariana. 
Of these species the following four have been detected in Suffolk County, 
Long Island: Desmodium (Meibomia) viridiflorum, Rubus cuneifolius, Ipomoca 
pandurata, Phlox subulata with the addition of sirteen species not mentioned 
previously: 
Drosera filiformis. Helianthus angustifolius. 
Coreopsis rosea. 
Utrieularia subulata. 
Chamaecyparis ee 
Juncus pelocarpus 
Xyris caroliniana. 
Ascyrum stan 
es F polen 
E. leucolepis 
E. album. 
Aster Aa 
Solidago pube 
Chrysopsis m 
Di 
thyoides. 
Eleocharis melanocarpa. 
Sporobolus serotinus. 
Thus it appears that 34 of these characteristic pine barren plants grow in 
the southern part of Staten Island, and that 46 of them have been detected 
in Suffolk County, Long Island. 
It would seem that these species have followed the two more recent geo- 
logie formations, throughout their whole extent along the Atlantic coast. An- 
other fact which stands out prominently in this connection is that not a single 
one of the above mentioned plants, growing as we have seen along the edge 
of the glacial drift is native of Europe, but belongs to a true American flora, 
which had its origin in the southern part of the continent and migrated north- 
ward into Staten Island and Long Island at the close of the great ice age. 
In contrast to this fact, we have another one equally prominent and that is, 
that of the species of plants growing on the moraine and north of it about 
one-third are common to northern Europe and America. The flora north of 
the morainic lines clearly antedates in point of occupancy of the country the 
more southern and American pine barren flora, which migrated northward at 
a date subsequent to the migration of the flora with strong European affınity. 
It would seem that the flora of the Delaware Valley and of the coastal 
strip between the pine barrens and the salt marshes in New Jersey was 
