22 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



western United States. American botanists have created a number 

 of new genera for the reception of these, but they do not appear to be 

 generically distinct in the accepted sense, nor does this tend to faciUtate 

 their determination or the understanding of their relationships ; and 

 I have retained some of them {Cremnophila, Clemenisia, Sedaslrum, 

 Gormania) in Sedum, under which genus they were first described. 

 Some of the others (e.g. AUamiranoa, Dudleya, Slylophyllum, Villadia) 

 appear best placed in Cotyledon. 



Other generic names now included in the genus Sedum are Rhodiola 

 L. (now section Rhodiola) ; Anacampseros Tournefort (now section 

 Telephium) ; Procrassula Grisebach {= Aithales Webb. & Berth), a 

 small 5-stamened group included below in section Epeteium ; Telmissa 

 Fenzl, characterized by being one-seeded, but closely approached 

 in this respect by a few other species. 



The genus includes some well-marked groups, and others of less 

 definite boundaries ; these groups being founded mainly on general 



Fig. 3. — Floral Diagram of Sedum (after De CandoUe). 



growth-form. In the ensuing pages the generic subdivisions used, 

 and their definitions, are as follows : 



Section I. Rhodiola Scopoli (char, amplific). — Perennial. Root- 

 stock fleshy, crowned with leaves with a broad clasping base (often 

 reduced to membranous deltoid or semi-orbicular scales, or becoming 

 so with age), from the axils of which annual leafy flowering shoots 

 are produced. Flowers 4- or 5-parted, dioecious or hermaphrodite. 

 Hardy plants, mostly Asiatic. (P. 26.) 



Section II. Pseudorhodiola Diels. — Perennial. Flowers dioe- 

 cious, 4-parted, and otherwise as frequent in Rhodiola. Vegetative 

 parts and carpels as in Telephium. Hardy Chinese plants. (P. 73.) 



Section III. Telephium S. F. Gray. — Perennial. Rootstock 

 usually thick, branched, often of carrot-hke tubers, summit without 

 scales. Stems mostly annual, produced from buds beside or above 

 the bases of the stems of the previous year. Flowers hermaphrodite, 

 5-parted, white, red, purple, or green. Hardy plants, mostly Eurasian. 



(P- 77-) 



[Section IV. Giraldiina Diels. — ^Not in cultivation — two Chinese 

 species only.] (P. 107.) 



Section V. Aizoon Koch. — Perennial. Rootstock thickened, 

 roots slender. Stems annual (except S. hybridutn). Leaves flat. 



