PROCESSES WHICH OCCUR IN VEGETABLE TISSUES. 5 
together, and resting on a flattened subjacent phellogen; and 
similar ones are observable in the Hollyhoek ; and they may be 
assumed to be general in plants of the same longevity and like 
construction. 
I have seen no proper cicatricial formation of cork in the 
Bean (Faba vulgaris, Mill), whether grown under ordinary ex- 
posure or under the protective conditions of warmth and mois- 
ture. And it is perhaps true, generally, that the stems of 
herbaceous plants which last only one season, and in which no 
provision for leaf-fall exists, are incapable of such reparative 
process. 
Indeed, in the Bean, when grown under the usual conditions, I 
have seen no change whatever in the parenchyma,—at the most a 
lesser readiness of the cells beneath the surface to react under 
the iodine and sulphuric-acid test; but even this change is irre- 
gular and undefined. Frank also notices this absence of repair 
in the same plant. He speaks, however, of an outgrowth of cells 
or callus from the cambium. I have observed such an out- 
growth from the pericambium after amputation of the young root, 
but have seen no repair of an allied kind after removal of the 
stem, either in this or any other annual. 
In Eebalium, after amputation through the base of the young 
leaf-stalk, the ends of the fibro-vascular bundles killed in the divi- 
sion are raised from the deeper parts by the cell-multiplication. 
The spirals of the vessels may be found unrolled by the parti- 
tioning increase around, and stretched between the effete and the 
natural parts. In this way, by lateral compression, attenuation, 
perhaps rupture, the vessels are permanently closed beneath the 
temporary crust of sap. 
Leaving the effects of amputation in trees for later considera- 
tion, the case may be next considered of those plants which 
are intermediate in structure and longevity between herbaceous 
annuals and exogenous trees. One of the most convenient to 
take is the common so-called Geranium, Pelargonium sp. 
If a branch be removed near the parent stem, the cells injured 
by the division, together with several layers of those beneath, 
wither, and form atough buff-coloured membranous layer, beneath 
which the growth of the living parts uninterruptedly proceeds. 
The process of growth being maintained in the subjacent parts, 
the inextensible incrusting substance becomes cracked, and its 
fragments disparted and loosened from the growing parts beneath, 
