92 



THE LEAF 



TERMS USED IN THE DESCRIPTION OF LEAVES 



[Inserted for reference use by classes making the deternii'.Lation of 

 Dlants a part of their course.] 



167. Forms of leaves as to general outline. — It is necessary to 

 give names to the principal shapes, and to define them rather preciseh", 

 since they atford easy marks for distinguishing species. The same 

 terms are used for all other flattened parts as •well, such as petals; so 

 that they make up a great part of the descriptive language of Botany, 

 liegiiiuing with the narrower and proceeding to tlie broadest forms, a 

 leaf is said to be 



Linen- (Fig. S3), vhcn narro^n", several times longer than wide, and 

 of tlie same breadth throughout. 



Lanceolaie, or Lnnce-xliapcil, when conspicuously longer than wide, 

 and tapering upwards (Fig. til), or both upwards and downwards. 



Ohlimg (Fig. S.j), when nearly twice or thrice as long as broad and 

 of uniform breadth. 



Ellipliciil (Fig. SO), when similar to oblong but with continuously 

 rouiiiliug sides. 



Ofid, when broadly elliptical, or elliptical with the breadth con- 

 siderably more than half the length. 



Ornle (Fig. 87), when the outline is like a section of a hen's egg 

 lengthwise, the broader end toward the stem. 



-88. A series of sliajies of feathered-veined leaves: 8.T, Uuear; S4, 

 hmueolate; Sj, oblong; Sij, elliptical; 87, ovate; 88, cordate. 



Orbiculnr, or Botuml (Fig- 97), circular in outline, or nearly so. 



A leaf which tapers toward the base instead of toward the apex 

 may be 



(ililiiivriilitle (Fig. S!i), when of the lance-shaped form, only more 

 tapering toward the base than in the opposite direction. 



Spaluhile (Fig. 90), when more rounded above, but tapering thence 

 to a narrow base, like an old-fashioned spatula. 



Oborale (Fig. 91). when inverseh' ovate, that is, ovate with the nar- 

 rower end tiiward the stem. 



Cuneale, or Cmieifiinn, that is, Wedge-sha/ieil (Fig. 92), liroad above 

 and tapering by nearly straight lines to an acute angle at the base. 



