HARPER: PLANT POPULATION OF MICHIGAN 41 
many of the shrubs, vines and herbs have fleshy fruits.* Herbs 
with barbed fruits are in this region chiefly confined to rich woods 
and roadsides, probably partly because of the exemption of such 
places from fire,t though it is not at present apparent why that 
should affect them more than it does the fleshy fruits. (Barbed 
fruits seem to be more characteristic of warmer climates and more 
calcareous soils, too.) Plants with erect capsules on stiff stems 
which stand up through the winter (called “tonoboles” by 
Clementst) are much rarer here than a few degrees farther south, 
possibly because the snow interferes with their dissemination. 
About half the large trees are evergreen, but none of the small 
trees, vines and large shrubs are, strange to say. It would seem 
from this that no evergreens except conifers (and one of those is 
deciduous) can stand the Michigan winters without the protection 
of snow.§ Vines are scarce, only two being listed, and those are 
not found much farther north. 
The Ericaceae and allied families are largely represented among 
the small shrubs and evergreen herbs, as in many other places 
with similar climate. Other families pretty well represented in — 
proportion to the total number of species in them, or the total flora 
of this region, or both, are Equisetaceae, Cyperaceae, Orchidaceae, 
Salicaceae, Rosaceae, and Caprifoliaceae, while the opposite might 
be said of the Fagaceae, Cruciferae (native), Caryophyllaceae 
(native), Leguminosae, Polygalaceae, Violaceae, Hypericaceae, 
Umbelliferae, Labiatae, Scrophulariaceae, and Lentibulariaceae, 
The sedges seem to be more numerous and also more abundant 
than the grasses. 
Nearly all the species listed are widely distributed, extending 
from Nova Scotia to Minnesota at least, and most of them are 
represented in northern Europe by identical or closely related 
forms. Those peculiarly American plants which are confined to 
* See Torreya 14: 16. : 
(In the text on page 138 Allium and Deringa 
ional references 
that should have been given there are: S. M. Coulter, d 
1904; Harper, Torreya 10: 60-61. 1910. 
t. Surv. Neb. 7: 47. 1904 
§ In this connection see Gates, 
Acad. Sci. 1§: 194. 1914. 
Torreya 12: 257-262. 1912; Harper, Rep. Mich. 
