PAPERS ON BOTANY 111 
more than the customary leaf production of such bulbils, de- 
veloped into slender scapes—in one case, at least, two feet long, 
as freely floriferous and bulbil-bearing as the usual ultimate 
branches of a normal inflorensence. 
SOME PERCHED DUNES OF NORTHERN LAKE 
MICHIGAN AND THEIR VEGETATION 
Gro. D. Futter, University or CHICcAGo 
The sand dunes of the Lake Michigan shore may, for the pur- 
poses of our discussion be divided into groups according to 
their location. Those at the south end of the lake, situated 
principally in Indiana, differ in some respects from the sand 
areas scattered along the east shore upon the lower peninsula 
of Michigan. The formation of the Indiana dunes is in gen- 
eral more recent and is to be referred to that period during 
which the waters of the lake have stood at approximately their 
present level. A smaller portion of the area was developed 
during the later stages of the glacial Lake Chicago. 
In contrast with this the dunes of the lower peninsula of 
Michigan are to be associated with a more remote origin con- 
nected with bodies of water or ice belonging to former ages. 
It is the purpose of this paper to record a few of the 
phenomena connected with the occurrence of various dunes 
found upon the islands in the northern part of Lake Michigan 
and upon the adjacent mainland. 
Nearly all the dunes of this and similar regions are of 
lacustrine origin, being formed from sand thrown upon the 
shore by the waves and then caught up by the wind, carried 
inland, and piled in characteristic mounds and ridges. Some 
of these lacustrine dunes have accumulated upon the existing 
beach and may therefore be called beach dunes, while others 
are developed upon substrata elevated some distance above the 
beach and may be termed perched dunes. They may have been 
formed either by a wind eddy at the top of a short cliff, or have 
travelled inland from the beach over higher land. The term is 
