48 VEGETABLE ORGANOGRAPHY. 



The immediate envelopes are the Corolla, which is of 

 an analogous nature to the genital organs ; and the 

 Calyx, which serves as the external covering, and is of 

 a foliaceous nature. To these four organs must be added, 

 for the sake of clearness, the Torus, which serves as 

 the common base of the corolla and stamens ; and the 

 Axis, which is the prolongation of the pedicel. These 

 six parts spring from the top of the pedicel, and consti- 

 tute all the essential organs of the flower. All that is 

 found outside the calyx, belongs to the bracts or invo- 

 lucra, which I have already mentioned ; and that which 

 is met with in the interior, and does not form part of 

 these six organs, is reduced to some nectariferous glands 

 which do not appear essential to the flowering. 



We shall first describe each of these parts in its most 

 simple and least complicated state, joining only to their 

 description the cohesions* which they contract. We 

 shall examine the modifications which they present, in 

 their adhesions, abortions, or affinities with neighbour- 

 ing organs ; and we shall conclude with some observa- 

 tions upon the whole structure of flowers. 



Section II. 



Of the Calyx or Sepals. 



The Calyx is the external envelope, usually folia- 

 ceous, which is observed in almost all complete dico- 

 tyledonous flowers, and which forms the sole envelope 



* From analogy with medical language, I call Cohesions the unions 

 of organs of the same nature, and Adhesions those of different organs : 

 thus the sepals united together are Coherent ; united to the ovarium, 

 Adherent. 



