216 BUDS AND STIPULES 



that in this case, as in that of the Cucumber, there has 

 been, and is still, much difference of opinion. 



The ligule of grasses is another doubtful case, but 

 must, I think, be regarded as a form of stipule. 



The leaf of a grass may be divided into three 

 parts the sheath, the blade, and the ligule. The 

 sheath embraces the stem ; at the point where it termi- 

 nates are two blades, one, generally called the leaf, 

 making a broad angle with the stem, the other being 

 a prolongation of the sheath, and known as the ligule. 



It must, therefore, I think, be admitted that some 

 Monocotyledons do possess stipules ; and having regard 

 to the great differences presented by the two classes, 

 we cannot, I think, be surprised that the stipules of 

 Monocotyledons generally differ considerably from those 

 of Dicotyledons. 



STIPELL^E 



The leaflets of pinnate leaves have sometimes a 

 small foliaceous expansion at their base, and for these 

 De Candolle proposed the appropriate name of ' stipels. 5 



Stipellse do not, like stipules, run generally through 

 a whole order, but are scattered sporadically in certain 

 genera and small groups of genera. Fig. 334 shows 

 an instance in a leguminous plant. 



EFFECT OF REMOVAL OF LEAF 



Goebel (9, 837), and subsequently Kronfeld (40), 

 have made some interesting experiments as to the effect 



