12 TRANSACTIONS OF THE hooray; 
fitted to the ground is destitute of marginal spikes. Second, 
the clustre of radial leaves is admirably disposed in position 
and succession * to cover accurately the extent of allotted 
ground, Third,the leafy petioles present a well designed run- 
way, passing from central bud to trap, which an insect is more 
than apt to follow as a method of escape, after it has run the 
gauntlet of trapping leaves. 
The actual disposition of the trap when, so to say, set, may 
thus be stated. The leafy petiole sprouts boldly upward, then 
descends gradually towards the trap. At first its face is narrow 
and flat, then its leafy margins begin to spread out laterally 
more and more until the trap is reached ; these leafy margins 
bend upward, often curling over, and thus form a creased run- 
way, admirably fitted to keep a visiting insect in the broad de- 
scending path. The leaf-stalk is decidedly springy it its back- 
ward curve, so much so that if its base be severed it writhes 
backward describing normally a curve of about 200°. Irri- 
tation of the stalk may thereafter cause the total flexure to 
become about 400°. This remarkable springiness appears to 
bring with it three important functions, (1) it causes the outer 
margin of the trap to be closely pressed to the ground—a 
position that is accommodated by the lamino-peliolar hinge, (2) 
it steepens the final descent of the runway, tending to prevent 
the retreat of visitors, and (3) it helps to adjust with nicety the 
leafy edges of the petiole to the sides of the trap and prevents 
interstical ese capes. | The ascending portion of the runway 
has been carefully examined for aids to climbers, but these do 
not apparently oceur. There are no hairs even along the mar- 
gins, the ascent is smooth, a bit vascular, a condition perhaps 
of advantage to the padded feet of visitors. This moistness is 
somewhat viscid, judging from the dust and minute granules 
usually adherent. The trap itself in its disposition appears to 
be singularly adapted to its environment, not merely in the 
degree in which it opens but in the concavity of its lobes and in 
the bend of its marginal spikes. In the position commonly 
assumed the tip of the trap rests upon the ground, the lobes 
arching slightly upward are inclined to each other at an angle 
of about 50°, their concavity is well marked, the spikes inclin- 
ing slightly inward. This position appears to be the one of 
* C.F. Lubbock, Leaves, Flowers and Fruits, in regard to leaf disposition for 
other functions, e. g., respiration. 
+ The position of the trap, the degree to which it is open, the amount of bend- 
ing of the joint, seem to determine the nicety of the adjustment of the springy 
margins—these, when the angle between petiole and blade, becomes marked, are 
usually closely opposed to the inner face of the trap, often in this way forming 
a kind of leafy funnel, 
