LECT. XI.] CAULINAH AND FOLIAR APPENDAGES. 663 



which in some instances accompanies the proper 

 leaf, yet is distinct from it : and, in others, is at- 

 tached to the petiole, appearing as a part of the 

 leaf itself*. It is not a universal and not always 

 a permanent organ. In some instances it is fuga- 

 cious (fugax, caduca), accompanying the leaves in 

 the bud only, and falling at the moment of their 

 evolution, or before they are fully expanded ; as 

 is the case in the Lime tree, Tilia Europcea, and 

 the Tulip tree, Liriodendron tulipifera: in others 

 it is deciduous (decidua), or falls with the leaf, 

 which is the most common occurrence ; but in 

 this case it occasionally appears withered (mar- 

 clda) before the leaf falls, although it remains at- 

 tached: and in others again, it remains after the 

 natural fall of the leaf, or is persistent (persist ens), 

 as in Downy Sea-side Grape, Cocoloba pubescens. 

 Stipules vary in size, number, form, substance, 

 and situation, in different plants; and these diversi- 

 ties constitute, occasionally, excellent specific dis- 

 tinctions. The presence or the absence of stipules 

 has, also, been regarded as an indication "that 

 " plants belong to the same natural order and even 

 " genus ;" but Sir E. J. Smith has justly remarked 

 this is not invariably the case. " Some species of 

 " Cistus have stipulas, others none, which is nearly 



* " Stipula est squama, quae basi petiolorum aut peduncu- 

 ** lorum enascentium utrinque adstat." Phil. Bot. 84. 1 . 



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