CHAPTER IX 
THE CROWFOOT FAMILY 
101. General features. In several respects the crowfoot 
family is the best one with which to begin our study of plant 
groups. It forms an especially serviceable standard of com- 
parison because its members, as we shall see, are remarkably 
simple in their plan of structure—at least for seed-plants— 
and at the same time the various species display a wide range 
of variety in detail. Moreover, it was his careful study of 
this family which led the younger Jussieu to an understanding 
of those fundamental principles of classification which he 
applied so brilliantly in founding the natural system. To us 
it will present problems which once solved will simplify and 
illuminate all our future study. 
Of the plants already examined the following, as we have 
seen, are of this family: marsh-marigold (Caltha palustris, 
page 198), tall buttercup (Ranunculus acris, page 216), 
ditch crowfoot (R. sceleratus, page 216), wind-flower (Ane- 
mone nemerosa, page 205), and monkshood (Aconitum 
Napellus, page 191). The family is made up of about 700 
species in about 30 genera. From the few examples above 
given and a study of those shown in Figs. 282-297, we may 
gain, however, a fair idea of the range of peculiarities exhib- 
ited by the family as a whole. At first sight it may seem 
scarcely possible to find among plants which differ so much 
- one from another any peculiarity or set of peculiarities 
common to all and yet not possessed by other seed-plants. 
Examination will show us, however, that as a group they 
may be distinguished at least by the lack of complicating 
features which other families show, and we shall find further- 
more a few positive peculiarities which are more or less 
characteristic. 
328 
