405 
Geophilous Species of Peperomia . 
Externally the fruit appears pitted or corrugated, and has a short dome-like 
stigmatic cap x , which is in great contrast to the nearly smooth fruit of 
P .. peruviana with its relatively long stigma (cf. Fig. 3, PI. XXIX) 2 . In section 
the fruit-wall is composed of four or five internal layers of parenchymatous 
cells more or less alike, though the cells of the layer next the integument 
tend to be tangentially elongated. The outermost or epidermal layer con- 
sists of thick-walled square or oblong cells interrupted by frequent pits, at 
the base of which are the gland-cells (Figs. 18-20) — groups of four cells 
in the tissue of the pericarp, with peculiar contents, some of which stain 
blue with Water Blue and appear to be of a mucilaginous nature, whilst 
others remain unstained and are highly refractive. The stigmatic knob 
is made up of a group of reticulately thickened sclerous cells. I was 
unfortunate in not securing any seedling stages of this species, and the ripe 
fruits which were collected in Bolivia would not germinate on my return 
home. One germinated seed, however, was discovered in my material 
which still enclosed the lamina of the absorbent cotyledon. The petiole of 
this cotyledon, which was broken off from the rest of the seedling, is much 
longer and stouter than is the case in P . peruviana (Fig. 21, PI. XXIX). 
On dissecting away the seed, the lamina of the absorbent cotyledon 
was found to be obovoid or club-shaped, about -45 mm. in length by -35 mm, 
in breadth, having a circular outline in transverse section. There were 
apparently no stomata, though this point is somewhat uncertain. The 
more highly specialized character of the absorbent organ in this species 
is of considerable interest, for the adult plant is of a much more xerophytic 
type than P. peruviana , and it seems probable that the lamina of the aerial 
cotyledon is withdrawn in a rudimentary condition from the seed at an early 
stage in the germination, and thus gives room for the development of 
the hypogeal cotyledon to join the aroid-like absorbent organ (vide Text- 
figs. 5 and 6, p. 420), which then completely fills the cavity of the endosperm 
(cf. Text-figs. 3 and 4, p. 420). 
Of bulbs with the first, second, or third, &c., plumular leaves, several 
were collected, and from the nature and position of the leaf-scars there can 
be no doubt that a very similar course of development obtains to that 
already described (Figs. 23-25). The young bulbs are readily recognized 
by their size and their whiteness, and by the fact that the roots, which are 
long and much branched, are produced only from the base (Fig. 23). In a 
transverse section the epidermis of the bulb is seen to be protected by a thin 
cuticle, which stains light yellow with Iodine, but there is no formation of 
cork. The cortical cells, as in P . peruviana, are filled with starch, but whilst 
in that species the starch-grains are more or less rounded and small, they 
are here considerably larger and ovoid. The plant is a much more pro- 
nounced xerophyte than P. peruviana (Fig. 27), and this is very well seen 
1 Cf. Dahlst. , 1. c., PI. I, Fig. 7. 2 Da hlst., 1. c.,. PI. I, Fig. 9. 
E e 2 
