368 PINGUICULA VULGARIS. Cnar. XV 
CHAPTER XVI. 
Pinavictba, 
Pinguicula vulgaris —Structure of leaves — Number of insects and 
other objects caught — Movement of the margins of the leaves — 
Uses of this movement — Secretion, digestion, and absorption — 
Action of the secretion on various animal and vegetable substances 
—The effects of substances not containing soluble nitrogenous 
matter on the glands — Pinguicula grandiflora — Pinguicula lusi- 
tunica, catches insects—Movement of the leaves, secretion and 
digestion. 
PINGUICULA VULGARIS.—This plant grows in moist 
places, generally on mountains. It bears on an average 
eight, rather thick, oblong, light green leaves, having 
scarcely any footstalk. A full-sized leaf is about 14 
inch in length and # inch in breadth. The young 
central leaves are deeply concave, and project upwards ; 
the older ones towards the outside are flat or convex, 
and lie close to the ground, forming a rosette 
from 3 to 4 inches in diameter. The margins of the 
leaves are incurved. Their upper surfaces are thickly 
covered with two sets of glandular hairs, differing in 
the size of the glands and in the length of their 
pedicels. The larger glands have a circular outline as 
seen from above, and are of moderate thickness; they 
are divided by radiating partitions into sixteen cells, 
containing light-green, homogeneous fluid. They are 
supported on elongated, unicellular pedicels (contain- 
ing a nucleus with a nucleolus) which rest on slight 
prominences. The small glands differ only in being 
formed of about half the number of cells, containing 
much paler fluid, and supported on much shorter pedi- 
cels, Near the midrib, towards the base of the leaf, the 
