10 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



The most marked feature of the Sedum flora is the occurrence 

 in the west of a well-marked group of small perennial species with 

 spathulate leaves and mostly yellow flowers, of which S. spathuli- 

 folium and S. oreganum, already referred to, are examples. Some 

 of these have the petals joined together in the lower portion (thus 

 approaching the genus Cotyledon), and have been separated on this 

 account from Sedum by some American botanists ; but I have 

 preferred to retain them in that genus. 



Literature. — Britton and Rose, " Crassulaceae," in " North 

 American Flora." 22, Part I., 1905. 



Mexico. 



Mexico, which is now known to be extraordinarily rich in Sedums 

 and other Crassulaceae, was until recent years a terra incognita. 

 Two species of Sedum, moranense and oxypetalum, were described 

 in 1823 among the plants collected on Humboldt's voyage (vol. 6, 

 pp. 44, 45), and five years later De Candolle included two more, 

 dendroideum and ebracteatum, in his " Memoire sur la famille des 

 Crassulacees " (1828). As a result of herbarium work carried out in 

 connexion with the great "Biologia Centrali- Americana," Hemsley 

 was able, in 1879-88, to enumerate 22 species from Mexico in the 

 first volume of the botanical section of that publication. During 

 the last thirty years the explorations of a number of United States 

 botanists have resulted in the disc9very of a surprising number of 

 new and interesting species of Sedum and of closely allied plants for 

 which new genera have been created, though in a broad sense many 

 of them may be ranked as Sedums ; so that the species known from 

 Mexico is now verging towards a hundred. Living plants of many 

 of these have been sent to the States by their collectors, and are 

 in cultivation at Washington and other places. They are still almost 

 unknown in British and other European gardens, though many of 

 them are handsome and interesting plants, strikingly different in 

 appearance from any of the Old World Sedums. By the kindness 

 of American correspondents, notably Dr. J. N. Rose (the describer 

 of most of the new species) and Dr. N. L. Britton, I have received 

 living specimens of a large number of these species. Plants of all or 

 nearly all of them have now been placed at Kew, Edinburgh, and 

 Dubhn (wherever they were not already represented in the collections), 

 and we may hope that these interesting species will now become 

 better known on this side of the Atlantic. They display a remark- 

 able range of form, from stout shrubs several feet in height, such as 

 oxypetalum and praealtum, to tiny creeping species like compactum 

 and humifusum ; the leaves show every variety of shape and size, 

 and the flowers range through almost every hue. Many of the species 

 are striking and decorative plants, such as alamosanum, cupressoides, 

 Stahlii, Palmeri, helium, nutans, pachyphyllum, and versadense. 



