4()G JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Bryophyllum. — A small genus well marked by the inflated calyx. 

 The flowers are usually dull in colour, but by good cultivation the plants 

 may be made ornamental. B. proliferum (" Bot. Mag.," t. 5147) is 

 sometimes known as the "air plant," leaves when hung up being capable 

 of producing buds in the crenatures. For that reason, also, the plant is 

 held to illustrate the nature of the carpellary leaf, the young plants 

 appearing at the edge of the leaf in the place of the ovule. 

 B. calycinum (" Bot. Mag.," t. 1409), which extends from tropical 

 Africa into Asia, is often found in gardens. 



Kalanchoe. — A genus with several good species belonging to South 

 Africa, but with its best horticultural exponents in Somaliland, 

 Abyssinia, and tropical Africa. It differs from Cotyledon in having 

 quadripartite flowers, and to no other genus has it any particular resem- 

 blance. K. carnea, a few years ago, was much grown. K. thyr&iflora, 



Fig. 81. — Cotyledon coruscans. 



figured from Cambridge in the " Bot. Mag." (t. 7678), has remarkably 

 Cotyledon-like foliage. 



Cotyledon. — A large and important genus, including ornamental and 

 also curious species. It is distinguished among allies by having a quinque- 

 partite calyx, often much shorter than the corolla, ten stamens, and five 

 connate petals forming a tube. The leaves are almost always opposite, 

 and all are natives of the Cape. Echevcria, which, most inconveniently, 

 I think, has been united with it, is not found at the Cape. The leaves 

 are alternate, very often arranged in a rosulate manner ; the calyx is 

 often foliaceous and often longer than the corolla.* Among the most 



* When plants are geographically distant, distinct in aspect, and without inter- 

 mediates, it should be philosophically correct not to rely upon floral difference hut to 

 seek for characters in the vegetative organs. Among all the hybrids of EcJieveria 

 there is not one, 1 believe, with Cotyledon. A systematic arrangement is chiefly for 

 convenience, and no purely scientific interest is interfered with by giving a generic 

 name to every conspicuously distinct set of plants. 



