CHAP. II. CALYX. 1(3.5 



the same time acquires the property of twining round any 

 body within its reach, and so of supporting the stem, which 

 is too feeble to support itself. Such rachises form wluit is 

 called a spurious cirrhus, or a cirrhus j}edunciilaris, and are a 

 striking exception to the general law that the cirrhus takes its 

 rise from the petiole or midrib. 



6. Of the Calyx. 



The calyx is the most exterior integument of the Flower, 

 consisting of several verticillate leaves, either united by their 

 margins or distinct, usually of a green colour, and of a ruder 

 and less delicate texture than the corolla. 



Authors have long disputed about the definition of a calyx, 

 and the limits which really exist between it and the corolla : 

 the above, w^hich is copied from Link, seems to be the only 

 one that can be considered accurate. The fact is, that in 

 many cases they pass so insensibly into each other, as in Caly- 

 canthus and Nymphaea, that no one can say where the calyx 

 ends and the corolla begins, although it is evident that both 

 are present. Linnaeus, indeed, thought that it was possible 

 to distinguish them by their position with regard to the 

 stamens, asserting that the divisions of the calyx are opposite 

 those organs of the corolla alternate with them ; but, if this 

 distinction were admitted, the corolla of the Primrose would 

 be an inner calyx, which is manifestly an absurdity. Jussieu 

 defines a caljTC by its being continuous with the peduncle, 

 which the corolla never is ; and this may seem in some cases 

 a good distinction ; but there are plenty of true calyxes, of all 

 Papaveraceous and Cruciferous plants, for instance, in which 

 the cal}TC is deciduous, and not more continuous with the 

 peduncle than the corolla itself. The only just mode of dis- 

 tinguishing the caljTC seems to me to be to consider it in all 

 cases the most exterior verticillate series of the integuments 

 of the flower within the bracts, whether it be half-coloured, 

 deciduous, and of many pieces, as in Cruciferse ; membranous 

 and wholly-coloured, as in Mirabilis ; green and campanulate, 

 or tubulai', as in Laurus and Lythrum. Upon this principle, 

 whenever there is only one series of floral integuments, that 



K 4 



