Hill . — A Revision of the Geophilous Species of Pep eromia. 145 
To the former type belong P. peruviana , P. falsa , P. Gaudichaudii , 
P. ovato-peltata , P. claytonoides , and P . pedicellata (PI. XV, Figs. 9 and n), 
whilst P. parvifolia , P. verruculosa , P. cyclaminoides , P. hracteata , and 
P.campylotropa (PI. XV, Figs. 36 and 17) possess the more xerophytic type 
of fruit characteristic of the second group. The fruit of P. inonticola 
(PL XV, Fig. 12) is quite distinct from either type, and will be described later. 
In all cases the pericarp, which is some three to six cells in breadth, 
is bounded by a more or less thickened layer of cells, interrupted by pits, 
and it is these pits which give the surface of the fruit its characteristic 
appearance. In the group of which P. peruviana may be taken as a type, 
the walls of the external layer of pericarp cells are not much thickened, 
but the cells of this layer tend to be elongated tangentially, and the pits 
are broad and shallow. At the base of each pit there is a gland, consisting 
of a single cell with peculiar refringent contents L The pericarp is usually 
about three to four cells broad, and the cells contain chlorophyll. When 
the seed is ripe the cell-walls are often found to have become blackened. 
The style in this group is usually a somewhat narrow conical or cylindrical 
organ bearing the stigma at its apex, and in P. mexicana and P. macrandra 
it attains to a considerable length 1 2 . 
In the xerophytic group, of which P. parvifolia is a good example, 
the pericarp is seen in section to be some five or six cells in breadth ; 
the walls of the outermost layer of cells are more or less strongly 
thickened, and the cells themselves may be isodiametric or radially 
elongated 3 . 
In some of the species the cells of the outermost layer are more or 
less isodiametric, as in P. minuta (PI. XV, Fig. 7), whilst in others they are 
radially elongated, e. g. P. verruculosa 4 and P. cyclaminoides . The innermost 
layer of cells next the testa is composed of large and tangentially elongated 
cells in some species. The glands at the base of the pits may be large 
single cells, as in P. minuta (PI. XV, Fig. 7), P. bracteata , P. campylotropa , 
or they may be composed of a group of four or more cells, as in P. parvi - 
folia, P. verruculosa , P. cyclaminoides (PL XV, Fig. 17), where they form 
conspicuous structures. The style in all these species is a small dome-like 
button at the apex of the fruit with the stigma at its summit. The fruit 
of P. inonticola is peculiar in the black polished and faceted appearance 
of the surface of the pericarp. In section also it differs from the other 
geophilous species in the greater development of the pericarp, of which the 
basal part of the fruit is entirely composed (PL XV, Fig. 12). The outer- 
most layer of the pericarp consists of thick-walled and very regular 
isodiametric cells, interrupted by narrow and not very deep pits, and this 
causes the peculiar faceted appearance of the fruit-walh 
1 Hill, 1 . c., p. 400, PI. XXIX, Fig. 4. 2 Ibid., 1 . c., PI. XXX, Figs. 43-47. 
3 Ibid., 1 . c., p. 405, PI. XXIX, Figs. 19-20. 4 Ibid., 1 . c., PI. XXIX, Fig. 29. 
