OF THE LEAVES. 459 
thus altered, but the following species appear to be 
particularly subject to this change : Asculus Hippocas- 
tanum, Digitalis purpurea, Morus alba, Fagus silvatica 
contracta (hort.), Codiwum variegatum var. eroswm 
(hort.), Broussonettia papyrifera, Scolopendrium vulgare, 
&e. 
Frequently this irregular diminution in proportion 
is coexistent with an unusual degree of cleavage or 
laciniation of the margin, as in Acer platanoides lacinia- 
tum, Tilia asplenifolia, Alnus imperialis (hort.), Fagus 
silvatica var. (hort.), &e. 
In the case of what are sometimes termed interrupted 
leaves, the laminar portions of the leaf are here and 
there deficient on both sides of the midrib, leaving 
small portions of the latter, as it were, denuded and 
connecting the segments of the laminez one with the 
other. This has been observed amongst other plants 
in Veronica latifolia, Broussonettia papyrifera, Codieum 
variegatum var. interruptum (hort.), Scolopendrium vul- 
gare, &c.’ (See p. 328.) 
In some of the leaves which have been already re- 
ferred to in illustration of the mordinate growth of 
the cellular portions, the mcreased development of 
parenchyma is associated with a contracted state of 
the midrib and its branches, producing a puckered 
appearance of the leaf, an exaggerated degree of that 
change which produces what are termed “ folia bul- 
lata.” In illustration may be cited various species of 
Mentha, Perilla, Coleus, Fagus silvatica crispa, Cytisus, 
Laburnum var., and other forms, cultivated in gardens 
for their singularity. 
Entire absence of the stalk of the leaf occurs nor- 
mally in sessile leaves; on the other hand the blade of 
the leaf is only occasionally developed in the phyllodi- 
neous Acacias, in some species of Ozalis, Indigofera, 
Tebeckia, Ranunculus, Bupleurum, &e. 
1 On the subject of this paragraph the reader may consult A. Braun, 
“Ueber abnorme Blattbildung,” &c., in ‘ Verhandl..’ d. 35, ‘ Naturfor- 
scherversammlung ;’ Jaeger, ‘ Flora,’ 1850, p. 481, tab. 4, Digitalis. 
