LECT. XI.] CAULINAR AND FOLIAR APPENDAGES. 629 



parating a peculiar fluid, embedded in the cellular 

 substance, or half sunk in the cutis, and, if elevated 

 above its surface, displaying great diversities of 

 form, its exceptionable character is evident. In 

 rejecting, however, this definition, the difficulty 

 of forming an appropriate one must be acknow- 

 ledged. A definition formed altogether on the 

 existence of the secretory function, would occasion 

 us erroneously to regard as glandular any part 

 where the presence of a fluid, distinct from the 

 common juices of the plant, might lead us to sus- 

 pect the operation of that function, although the 

 part should display no organic peculiarity sufficient 

 to authorize the application of the term gland to it. 

 On the other hand, a definition founded on struc- 

 ture alone, or on figure or position, would lead us 

 as far astray. Perhaps we shall arrive nearer the 

 truth if we take into consideration both structure 

 and function, and say that a vegetable gland is a 

 minute organ, differing in structure from the com- 

 mon texture of the part where it is situated, and 

 separating some peculiar matter from the ordinary 

 v eg eta b le fluids. 



Guided by this definition, we find glands on the 

 stem and leaves, situated both under the cutis and 

 on its surface. In describing these organs some 

 arrangement is necessary ; and in looking into 

 books to know what has been done in this way, 

 we find that the arrangement proposed by Guet- 



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