Cuar. XVII. STRUCTURE OF THE LEAVES. 447 
round the cylinder like a thread round a screw. If the 
cylinder is now removed, we shall have a tube like one 
of the spiral arms. The two projecting edges are not 
actually united, and a needle 
can be pushed in easily be- 
tween them. They are in- 
deed in many places a little 
separated, forming narrow 
entrances into the tube; 
but this may be the result 
of the drying of the speci- 
mens. The lamina of which 
the tube is formed seems 
to be a lateral prolongation 
of the lip of the orifice; 
and the spiral line between 
the two projecting edges is 
continuous with the corner 
of the orifice. If a fine 
bristle is pushed down one 
of the arms, it passes into 
the top of the hollow neck. 
Whether the arms are open 
or closed at their extre- 
mities could not be deter- Fic. 29, 
a . (Genlisea ornata.) 
mined, as all the speemmens Utriculiferous leaf ; enlarged about 
were broken; nor does it three times, 
. t Upper part of lamina of leaf. 
appear that Dr. Warming 5 Utticleor bladder. 
é ay GS Neck of utricle. 
ascertained this point. yoni, 
Spirall d arms, with theit 
So much for the external *% "nisbokenof 
structure. Internally the 
lower part of the utricle is covered with ‘spherical 
papillee, formed of four cells (sometimes eight accord- 
ing to Dr. Warming), which evidently answer to the 
quadrifid processes within the bladders of Utricularia. 
