separate the species of the three geographical areas. In the best- 
known European species, C. Umbilicus (Umbilicus pendulinus, 
D.C.), for instance, there is a perfectly tubular corolla, with lobes 
that do not reach above a quarter of the way down, and a calyx 
not more than a quarter as long as the tube. But the Pyrenean 
U. sedoides, D.C., has a campanulate corolla sht nearly to the 
base, with a calyx half its length; and the Siberian U. spinosus, 
malacophyllus and leucanthus, and Himalayan U. oreades and 
spathulatus, have also the petals as nearly free as in the 
American plants, and the calyx in some of them is quite as long 
as the corolla. Many of the Asiatic species have cymose or 
paniculate flowers, and in the Siberian U. Lievenit we have a 
cyme, calyx and corolla quite identical with that of the American 
C. cespitosa. So that the three Candollean genera quite break 
down for want of characters, and it is the same with the more 
recently proposed Pachyphytum of Klotzsch; and we endorse 
cordially the view taken by Bentham and Hooker, in their 
‘Genera Plantarum,’ of the classification and nomenclature of 
these plants. 
So many of these American Cotyledons still remain unde- 
scribed, and the descriptions of the others are scattered so widely 
and drawn up with so little uniformity of plan that we have con- 
cluded that the only way of dealing with the plants effectually 
would be to pass all the New- World species under review, and to 
attempt to classify them in systematic order. ‘The following 
therefore is as complete a monograph as we can furnish of the 
American species, and we give figures, so far as we have been 
able to procure them, of those which have not been adequately 
figured already. 
§ Spicate. 
1. C. puBEscens (Baker). Longe caulescens, dense griseo-pubescens, 
foliis aggregatis, obovato-spathulatis, acutis, duplo longioribus quam 
latis, e basi tertii superioris spathulatim angustatis, utrinque pal- 
lide viridibus, ramorum floriferorum paueis, valde reductis, floribus 
15—25, subdense spicatis, bracteis linearibus, inferioribus floribus 
excedentibus, sepalis linearibus ineequalibus patulis, corolla flavo- 
rubra subequantibus. — Hecheveria pubescens, Schlecht. Linn. xiii. 
p- 411; Hort. Hal. t.9; Walp. Rep. ii. p. 295. 
Mexico. 
Stems grayish or reddish brown, like the rest of the plant 
between shaggy and velvety with gray pubescence, often one or 
