118 



ORGANOGRAPHY. 



BOOK I. 



are stronger than themselves. It was inckided by Linnaeus 

 among what he caWed fulcra ; and has generally, even by very 

 recent writers, been spoken of as a peculiar organ. But, as it 

 is manifestly in most cases a particular form of the petiole, I 

 see no reason for regarding it in any other light. It may, 

 indeed, be a modification of the inflorescence, as in the Vine; 

 but this is an exception, showing, not that the cirrhus is not 

 a modification of the petiole, but that any part may become 

 cirrhose. 



In some cases the petiole of a compound leaf is lengthened, 

 branched, and endowed with the power of twisting round any 

 small body that is near it, as in the Pea : it then becomes what 

 is called a cirrhus petiolaris. At other times, it branches oft on 

 each side at its base below the lamina into a twisting ramifi- 

 cation, as in Smilax horrida ; when it is called a cirrhus pe- 

 duncularis. At other times it passes, in the form of midrib, 

 beyond the apex of a single leaf, twisting and carrying witl 

 it a portion of the parenchyma, as in Gloriosa superba ; when 

 it is said to be a cirrhus foliaris. De Candolle also refers to 

 tendrils the acuminate, or rather caudate, divisions of the 

 corolla of Strophanthus, under the name of cirrhus corollaris. 



As another modification of the petiole, I am disposed to 

 consider with Link (Elem. 202.) the singular form of leaf in 

 Sarracenia and Nepenthes {Jig. 58.), which has been called 

 a pitcher [Ascidium, Vascidum outre De Candolle). This con- 

 sists of a fistular green body, occvipying the place and per- 

 forming the functions of a leaf, and closed at its extremity by 



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