THE COROLLA. ^ 199 



itself. Dr. Darvviii calls the Corolla the lungs of the 

 stameiis and pistils, and with great probability, for they 

 abound in air-vessels. But when we consider the ela- 

 borate and peculiai' secretions of a flower, the elastic 

 inflammable /;o//e/7, the honey, and the exquisitely vo- 

 latile perfume, as we know from the curious discoveries 

 of modern chemistry how great a share light has in 

 the production of such, we cannot but conclude that 

 the petals must be of primary importance with respect 

 to their secretion by its means. 



Sometimes the Corolla is very short-lived ; sometimes 

 very lasting, even till ihe fruit is perfected, though 

 mostly in a fad ech condition. In double flowers I have 

 observed it to be much more durable than in single 

 ones of the same species, as Anemonies and Poppies, 

 because, as I conceive, of its not having performed ts 

 natural functions, the stamens and pistils of such 

 flowers being obliterated, or changed to petals ; hence 

 the vital principle of their corolla is not so soon ex- 

 hausted as usual. PhiL Trans, for 17SS, p. 165. 



The Corolla, as already mentioned, is not essential. 

 Whatever its functions may be, they can be occasionally 

 performed by the Calyx perhaps, or even by the Fila- 

 ments of the Stamens ; as those of leaves are, in leaf- 

 less plants, by the stems. When a flower has only 

 one covering,, it is not always easy to say whether that 

 be a Calyx or Corolla. When green and coarse in 

 texture, like the former, we call it so, as in Chenopo- 



