CHAP. II. 
LEAVES. 
137 
united, so that the blade is composed of several distinct parts 
combined by the midrib only, the distinct portions or lobes 
are called segments. They differ from the leaflets of more 
compound leaves merely by the circumstance of not being 
jointed with their support, nor deciduous. A leaf having 
such segments is called dissected. 
“ If the lobes are united near the base around the origin of 
these veins, we name them partitions, and the leaf is said to 
be parted. 
“ Supposing the lobes to be united as far as the middle, 
they become divisions, their recesses are fissures, and the ad- 
jectives formed from these are made to end in fid, as midtifid, 
quinquefid, &c. ; this should not be applied to any cases in which 
the divisions extend below the middle of the veins ; it is, 
however, frequently applied to cases of a division as deep as 
the midrib. 
“ Finally, if the adhesion of the lobes is complete, and if 
the parenchyma which separates the extremity only of the 
veins is not extended to the extremity of the principal veins, 
or beyond them, the leaf is merely toothed (dentate)', the 
salient parts are toothings. When the toothings, or teeth, are 
rounded, they become crenels, and the leaf is crenelled (or 
crenate). This form of leaf is not very important, because it 
is not connected with the arrangement of the primary veins, 
while that of the lobes, already mentioned, always is. 
‘‘ The terms that express precisely the important subdivi- 
sions of the leaf are combined with those which indicate 
venation. Thus a feather-veined leaf (pennivenium) may be 
either pennatisected, or pennatiparted, or pennatifid, according 
as it has segments, partitions, or fissures. In like manner a 
palm-veined leaf (this is what I call radiating, p. 133.) may be 
palmatisected, palmatiparted, or palmatifid ; and so on. 
“ In like manner we say that a leaf is trisected, trifid, or 
triparted, when we would draw attention to the number and 
depth of the lobes of a leaf, rather than to the relation they 
bear to the veins. And, on the other hand, we may, by neg- 
lecting the number of the lobes, simply indicate their presence 
by saying that a leaf is pennatilobed, palmatilohed, and so on. 
‘‘The lobes themselves are sometimes subdivided upon the 
same principle as the leaf itself. We then say that a leaf is 
