44 MISSOURI BOTANICAL GARDEN. 
crowding on the shrubs, and back of these, the hemlock- 
maple-beech forest is encroaching on the conifers. Whit- 
ford* has alluded to the succession of forms in this and 
similar areas. The flora here is notably peculiar, being de- 
cidedly different from any other area on the same island 
and almost exactly similar to that found in like localities 
elsewhere in the United States and in Europe. Some of 
the noticeable features of these swamps are the follow- 
ing: — 
1. Large proportion of evergreens, both of the conifer- 
ous and broad-leaved types. 
2. Pronounced xerophytic flora, 7. e., a flora adapted to 
resist transpiration, the leaves ericoid or pinoid, often 
vertical, covered with glaucous bloom, rarely pubescent. 
3. Prevalence of carnivorous plants, Sarracenia purpurea 
and Drosera rotundifolia. 
4. Abundance of forms bearing fleshy fruits, well 
adapted to seed dispersal by birds. 
The much discussed question as to the prevalence of so- 
called xerophytic structures in these peat bogs is still an 
open one. Many suggestions have been made in the 
attempt to account for the apparent efforts of these 
swamp plants to protect themseives against loss of water 
by transpiration, while their environment seems to indicate 
that their water supply is unfailing and the adaptations 
for such protection unnecessary. It now seems probable 
that this ‘‘ xerophytic’’ structure is due to some other 
cause than the mere effort to protect against water loss. 
Kihlman f is of the opinion that the xerophytic structure 
belongs to northern forms which are exposed to strong 
* Whitford, H. N., The Genetic Development of the Forests of North- 
ern Michigan; A study in Physiographic Ecology. (Bot. Gaz. 31: 313. 
1901.) 
t+ Kini~Man, Pflanzenbiologische Studien aus Russisch-Lappland. 
(Acta Soc. pro Fauna et Flora Fennica, 6, (1890). 
