PRELIMINARY LIST OF THE MAMMALS OF NEW YORK 287 
The almost total absence of exact knowledge of the distribution of 
plants is especially apparent when an attempt is made to catalogue the 
more prominent species characteristic of the transition zone. While 
there are doubtless many species confined to this zone it is impossible 
with the data at hand to make any positive statement concerning them. 
The flora of the region occupied by the transition zone may be recog- 
nized primarily by the absence of the strictly boreal and austral forms, 
and secondarily by the mixture of northern and southern types of which 
it is composed. As in the case of the mammals and birds the austral 
elements predominate. The following southern flowering plants, among 
others, find their northern limit in some part of the transition zone: 
Pontederia cordata 
Trillium granadiflorum 
Trillium cernuum 
Lilium philadelphicum 
Smilax hispida 
Smilax herbacea 
Gyrestachys cernua 
Chamaecyparis thyoides 
Juglans nigra 
Ulmus fulva 
Ulmus racemosa 
Benzoin benzoin 
Sassafras sassafras 
Dianthera americana 
Conopholis americana 
Pentstemon hirsutus 
Datura tatula 
Datura stramonium 
Asclepias verticillata 
Asclepias tuberosa 
Azalea viscosa 
WVyssa aquatica 
Rhexia virginica 
Metbomia grandiflora 
Metbomia paniculata 
Crotalaria sagittalis 
Polygala polygama 
Polygala nuttallit 
pickerel-weed 
large-flowered wake-robin 
nodding wake-robin 
red lily 
hispid green-brier 
carrion-flower 
nodding ladies’ tresses 
southern white cedar 
black walnut 
slippery, red or moose elm 
cork or rock elm 
spice-bush 
sassafras or ague tree 
dense-flowered water willow 
squaw-root 
hairy beard-tongue 
purple thorn-apple 
Jamestown or jimson-weed 
whorled milkweed 
butterfly-weed 
swamp pink or honeysuckle 
large tupelo 
meadow-beauty 
pointed-leaved tick-trefoil 
panicled tick-trefoil 
rattle- box 
racemed milkwort 
Nuttall’s milkwort 
