PLANTS WITH TRAPS AND PITFALLS TO ENSNARE ANIMALS. 



131 



natural size in fig. 22. This Cephalotus also has two kinds of leaves, which are 



closely crowded in a rosette round the erect flower-stalk. Only the lower leaves 



of the rosette are transformed into traps for animals, and these are pre-eminently 



adapted for wingless creatures creeping upon the earth. The tankard-shaped 



traps all rest on the damp earth, and are furnished externally with borders or 



winged ridges, which facilitate the ascent 



of crawling animals to the mouth of the 



tankard. Flying insects are of course not 



excluded, and here again they are made 



aware from afar of the feast of honey 



provided by the presence of bright colours. 



The half-open lid is very prettily adorned 



with white patches and brilliant purple 



veins, and at a distance is readily mistaken 



for a flower. 



When small animals, whether with or 

 without wings, approach to take the 

 honey, they are so eager in their search 

 that they get upon the inner surface of 

 the mouth of the tankard-pitcher, which, 

 though fluted, is also very smooth and 

 slippery, and thence they easily slide into 

 the interior of the cavity. The pitchers 

 being half-full of liquid, most of the un- 

 lucky creatures die there in a short time 

 by drowning. But even if this were not 

 the case, they would never succeed in 

 working their way up to the light of 

 day. For every animal that wishes to save 

 itself from a Cephalotus pitcher has three 

 obstacles to overcome : first, a circular 

 ridge projecting inside the pitcher; sec- 

 ondly, a bit of wall thickly covered with 



little papillae, sharp, ridged, and pointed downward, the whole being comparable 

 to a flax-comb; and, lastly, on the involute rim round the mouth of the pitcher, 

 another fringe composed of hooked, decurved spines which bristle like an im- 

 penetrable row of bayonets in front of such animals as may have surmounted 

 the other difficulties. The abundance of the booty found at the bottom of Cepha- 

 lotus pitchers shows how efficiently these contrivances serve to prevent escape. 

 Ants, for instance, sacrifice themselves recklessly in their pursuit of honey, and 

 one often finds great numbers of them drowned in the liquid in the pitchers. The 

 prey is not in this case converted into a putrid liquor, but is partially dissolved by 

 a secretion having an acid reaction. This secretion is separated out by special 



Fig. 22. Cephalotus follicularis. 



