198 SECTIONAL ADDRESSES 
trap is completely relaxed. Then the door becomes quite convex, the 
lower part of the door resting on the threshold for a long distance (Fig. rr). 
In the set condition, the posture is reversed. The door, as viewed 
laterally, becomes distinctly concave, and only a relatively narrow strip 
along the door edge rests on the middle zone of the threshold, the edge 
abutting on the raised-up inner zone. It will be seen that this exactly 
parallels the case of U. cornuta. The profile of the trap as a whole shows 
similar changes, from which it is seen (Fig. 11) that the overhang above 
the entrance shares in the flexures which bring the door into the position 
of efficiency in the set condition. These observations rest on a careful 
examination of living material, using the same technique as in the case 
of other species, photographing the living trap before and after actuation, 
and thus obtaining profiles of the door and neighbouring parts. 
As compared with U. vulgaris, U. ceerulea is not so easily actuated, 
nor does it engulf air with the same readiness (Fig. 12). The entrance 
is narrow and the water film does not enter so readily, so that the trap 
may be exposed to air a long time before anything happens, if at all. 
While I have seen traps with air in them, I have not succeeded in seeing 
the spontaneous act. 
Tue Type U. MONANTHOS. 
The species of this type, which has never been seen elsewhere (volubzits, 
Menziesii, dichotoma, monanthos, violacea and Hookeri are known to me), 
are all Australasian. I am indebted to my genial correspondents, Mrs. 
Eileen R. Johnson, Mr. Allan McIntyre and Mr. A. V. Giblin, for excellent 
material. 
In form, the trap is peculiar and very distinctive, either almost circular 
in lateral view, or oval; but the distinction arises in the combination 
of form with two pairs of wing-like appendages, one pair running from 
the stalk to the lower angles of the entrance, the other on the shoulders 
of the trap leading to the upper angles of the entrance. Overhanging 
the entrance is a proboscis, downwardly curved over the front of the 
entrance. Specific differences are to be found in the greater or less 
amount of laciniation of the wings, etc. 
The approach to the entrance has, below it, a large patch of globose 
glandular trichomes, to act presumably as a lure. The entrance opening 
is circular, or nearly so, and is guarded by a thick, circular velum, some- 
what less ample above, arising from sessile trichomes lining the inner 
surface of the wall of the approach to the threshold proper. This circular 
velum is altogether peculiar to this group of species. The upper part of 
the door is so placed that it rests in contact with the circular velum,? its 
patch of low glands being exposed at the opening. The threshold is 
very deep and bends downward toward its inner border ; there is here no 
upturned surface to resist the thrust of the door edge. Indeed, the inner 
end of the door bends down over the ridge of the threshold. From inner 
angle to inner angle of the threshold the door, therefore, has a sharp 
permanent downward bend, the effect of which is to increase resistance 
5 I have, of course, not seen living material. It would take adequate study 
to be certain of the exact door posture in the living trap. 
