91 



tained. How else explain the fact that the bladder in the tripped 

 state can still take in water? 



There remain to be described the varied hairs that decorate 

 almost all parts of the bladders. Observation of these reveals the 

 fact that they all are built upon the same general plan, having three 

 cells as the fundamental unit. These may be termed basal, stalk 

 and head cells. On the outer parts of the trap the hairs are very 

 short and deeply sunken. In the porch they are long and slender 

 and on the door itself they are different again. (Withycombe 

 1924). 



Within the trap are hairs of two kinds. Scattered over the wall 

 are the so-called quadrifid hairs which have heads composed of four 

 radiating cells. It is supposed that these are digestive glands or 

 that they absorb water from the cavity and help to pass it to the 

 outside (figure 12). The other hairs are similar but are bifid and 

 are restricted to a limited area on the slope of the doorstep that 

 faces the cavity of the bladder. The upper surface of the step 

 itself (the 'doormat') is a closely packed layer of modified hairs 

 and it is the cuticle of these that forms by exfoliation the veil that 

 is adpressed to the door edge (Lloyd) (figures 2 and 3). 



We cannot doubt the power of Utricularia to kill and digest its 

 prey for we have seen time and again the death and digestion of 

 oligochaete worms and other animals. Death follows capture rela- 

 tively quickly, varying enormously, however, from trap to trap 

 and taking place most quickly, as far as our observations go, wdien 

 the victim is an oligochaete worm. As an example of the rapidity 

 with which the trap may repeat its feats we will quote but a single 

 case. A trap was observed to catch a large worm and was placed 

 on one side that we might watch the process of digestion. We 

 were surprised to find, after a lapse of thirty-five minutes, that 

 the bladder had captured a second, equally large victim. 



Death of a worm may take place in a couple of hours and in 

 less than a day nothing but a small amount of detritus remains. 

 The process is far too rapid for bacterial action to be responsible 

 for the change. 



This description has been confined almost in entirety to facts 

 and we pass now to the realm of history, fancy and speculation. 

 There is scope enough here as even a casual glance at the literature 

 will show. 



