BEBBEBIDAGE^J. 63 



or variable. Among the former characters we may note that the 

 leaves are alternate, but verticillate in one Erythrospermum; they lack 

 stipules, which however cannot be overlooked in several Lardizabalas; 

 they are compound or deeply lobed, but simple in Ert/throspermum, 

 Berberidopsis, and certain species of Berberis ; the perianth is usually 

 multiple (with calyx and corolla both double) ; but in Akebia it may be 

 reduced to a single whorl, and in Achlys it is quite absent ; the type 

 of the flower is ternary, but binary in most species of Epimedium ; the 

 staminal filaments are free, but united into a tube in about half the 

 Lardizabalece ; the anthers mostly open by valves, but are rimose in 

 Lardizabalece, Nandina, Podophyllum, and Erythrospermea ; the ovary is 

 pluriovulate, but contains only one ovule in Achlys. The characters 

 that vary from one genus to another are the habit and consistency 

 of the stems, the pinnate or digitate nervation of the leaves, the 

 inflorescence, the consistency and dehiscence of the pericarp, the 

 presence of an aril, and its mode of formation when present. 



In histological character Berberidacea present two distinct types 

 of organization, which one would hardly expect to find in the same 

 natural group, if one did not know that affinities of floral organiza- 

 tion do not carry with them identity of anatomical detail. The 

 first type is that of the Berberries and other woody plants of the 

 same group, whose organization may be easily studied in most of 

 the garden species of Berberis and Mahottia, as we have recently 

 done.' " The twigs of Berberis appear glabrous ; they are, however, 

 covered with conical or subcorneal hairs ; 2 which long persist, and 

 then turning brown with the epidermic cells, finally come off with 

 them, leaving the bark only protected by a sort of periderm found 

 within the superficial parenchymatous layers. Internal to this is a 

 yellowish green cellular layer, whose elements usually end by 

 parting company. They are cells, which then leave irregular 

 lacunae between one another. On the walls of these spaces may be 

 seen projecting either isolated cells or strings of unequal more 

 or less rounded cells. With age the contents of these cells may 

 disappear ; but then in several species the wall remains coloured a 

 bright yellow, and appears to be saturated with the same pigment 

 as is found in the liber fibres. In a transverse section of a young 

 branch we see a small circle of fibrovascular bundles separated from 



1 In Adansonia, ix. 320. - Especially in B. vulgaris. 



