44 STRUCTURAL AND PHYSIOLOGICAL BOTANY. 



346. But it is to be observed, that as there are no exact 

 limits between the corolla and the stamens (348), such bodies 

 as have been just described are often of an indifferent nature, 

 and may be referred with equal justice to petals passing into 

 stamens, and to stamens passing into petals. 



This is particularly the case with the fringes of Parnassia 198 , some parts of the 

 coronet of Stapelia 203 , the long rays of the Passion-flower. 



347. If, however, anomalous bodies at this part of the 

 vegetable system can be shown to belong to any whorl or 

 series of which a part is certainly petals or stamens, such ano- 

 malous bodies are to be regarded as belonging to the organ in 

 whose series they are placed. 



Thus in Aconitum 192 , the horn-like pro- 

 cesses belong to the series of the corolla, 

 and are therefore petals ; in the Ma- 

 hogany 202 , and in the Canna 205 , they 

 evidently appertain to the Andro3ceum 

 (348), and are therefore stamens. This 

 settles the true nature of what has been 

 called the nectary 206 , in Orchidaceous 

 plants, now termed the lip, or labellum, 

 which, forming a part of the second 

 series of floral envelopes, is therefore uni- 

 versally recognised as a petal, notwith- 

 standing its singular form. 



