314 DIONZA MUSCIPULA. Cuar. XIIL 
tissue) seems at first sight to favour this belief; for 
they run up the midrib in a great bundle, sending 
off small bundles almost at right angles on each side. 
These bifurcate occasionally as they extend towards 
the margin, and close to the margin small branches 
from adjoining vessels unite and enter the marginal 
spikes. At some of these points of union the vessels 
form curious loops, like those described under Drosera. 
A continuous zigzag line of vessels thus runs round 
the whole circumference of the leaf, and in the midrib 
all the vessels are in close contact ; so that all parts of 
the leaf seem to be brought into some degree of com- 
munication. Nevertheless, the presence of vessels is 
not necessary for the transmission of the motor 
impulse, for it is transmitted from the tips of the 
sensitive filaments (these being about the 7 of an 
inch in length), into which no vessels enter; and 
these could not have been overlooked, as I made thin 
vertical sections of the leaf at the bases of the fila- 
ments. 
On several occasions, slits about the +4, of an inch 
in length were made with a lancet, close to the bases 
of the filaments, parallel to the midrib, and, there- 
fore, directly across the course of the vessels. These 
were made sometimes on the inner and sometimes 
on the outer sides of the filaments; and after several 
days, when the leaves had reopened, these filaments 
were touched roughly (for they were always rendered 
in some degree torpid by the operation), and the 
lobes then closed in the ordinary manner, though 
slowly, and sometimes not until after a considerable 
interval of time. These cases show that the motor 
impulse is not transmitted along the vessels, and they 
further show that there is no necessity for a direct 
line of communication from the filament which is 
