STRUCTURE OF FLOWERS. 1 19 



cases where the usually foliaceous organs are found in a 

 petaloid state. 



The sepals frequently take the colouring and texture 

 of the petals. In this case, when the two organs coexist, 

 there is no doubt upon their distinction ; thus, the calyx 

 of a cultivated variety of the Primrose, Primula Calyc- 

 anthema, is expanded; into a coloured and petaloid 

 limb, so that the flower seems to have two corollas. 

 One of the lobes of the calyx of Mussoenda and Pink- 

 neya is dilated into a petaloid limb, whilst the others 

 retain their ordinary dimensions and appearance. In 

 several genera of theLeguminosse, Labiatae, Verbenaceae, 

 &c. the calyx is more or less coloured, without our being 

 likely to confound it with the corolla. But, if at the 

 same time that the calyx is coloured, the petals happen 

 to be wanting, or to take an unusual form, this calyx is 

 frequently taken for a corolla. This occurs in Anemone 

 and Clematis, where the petals are absent ; in Aquilegia 

 and Delphinium, where they exist, but deformed and 

 rudimentary. In all these cases, the calyx, although 

 coloured, is a true calyx, and it may be recognised 

 either by analogy with neighbouring genera where the 

 two organs exist, or by the study of double flowers. 



It sometimes happens that the bracts themselves, 

 although more distant from the petals, participate in the 

 same tendency, and are coloured wholly or in part, acci- 

 dentally or constantly ; but this phenomenon never 

 happens but when the calyx is coloured. Thus we find 

 now and then individuals of the Anemone, where the 

 involucrum is partly foliaceous and parti}' coloured : the 

 bracts of several Liliaceae, Leguminosae, &c, and the 

 involucra of several Umbelliferae present the same fact 

 more or less constantly. The bracts of Salvia splendens, 

 Monarda, and several other Labiatae, are ornamented 

 with the most beautiful colours. The involucrum of 



