MICHIGAN ACADEMY OF SCIENCE. 
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groups. The first group has very much thickened, fleshy roots, in allu- 
sion to which I have called it the Carnosae, or fleshy-rooted group. The 
second group has fibrous roots, for which reason I have called it the 
Fibrosae. Right here comes in another remarkable distinction between 
these groups The roots of the Carnosae, for example those of Helian- 
thus giganteus, have hitherto been considered as perennial, a notion 
which I had accepted up to June, 1911, but this is entirely erroneous. 
The crown of this group is perennial, but the roots are winter annuals. 
They are formed each year anew by the perennial crown and function as 
roots only during their first or formative season. During the latter part 
of that season they become thick and fleshy by the deposition of much re- 
serve material which is entirely consumed the next spring by the crown 
in the formation of new roots and the aerial stalks. Thus it will be 
seen that the roots, as roots have but one season’s existence, for during 
the second season they do not function as roots to an t y extent whatever, 
but simply as repositories of food for the new growth. The Fibrosae, 
chiefly a new group, are very different. The roots of this group are peren- 
nial. I will not say more about this group until after I have given it 
another season’s study. 
Sometimes the stems which grow from the lower buds of the crown 
of these plants, when obstructed in their upward growth by super- 
posed roots will work their way for a short distance under ground un- 
til they find an opportunity to take an upward course and emerge from 
the ground. At the point of emergence a fascicle of roots will be formed 
similar to that of the parent. The roots of these plants sometimes bud 
on the thickened part and send up an aerial stem which will form a new 
fascicle of roots. It is a characteristic of some of the species of this 
group that, if earth be piled high around the base of the stalks a 
new fascicle of roots will be produced above the old one. This is not 
the case with the migratorial group. 
Because of the fact that several stalks arise each year from the buds 
of the crown, and also that each stalk may and frequently does send 
out new roots, the jdants are clustered or caespitose. The ground 
around these clusters is packed full of these roots. In many of the 
Fibrosae the roots are interwoven and thickly matted. This is a general 
character of the whole group which distinguishes it very decidedly from 
the migratorial group. 
The technical name of the group I have therefore called Storeatae, 
which is derived from the Latin storea, a mat. The Storeatae, sub-group 
Carnosae, falls into two sections, as follows: 
Section 1. The Pinnatae, or plants whose leaves are pinnately veined. 
This section embraces the following old and Avell known plants besides 
several other species recently found in this state by the author. Their 
description will be given in the revision of the monograph. 
Section 2. The Trinervae, whose leaves are three-nerved after the 
manner of those of the great migratorial group which will be considered 
farther on. 
This is a large and very remarkable group of plants all of whose spe- 
cies now known were discovered by the author within the last four 
years chiefly during the autumn of 1910. It will thus be seen that 
this section is new to science. It divides itself into two well marked 
sub-sections in the following manner: Asperae which consists of plants 
