144 From Matter to Man. 



edges are rows of spikes which interlock when closed. 

 Each half of the leaf contains three filaments, sensitive 

 to the slightest touch. On an insect alighting and 

 touching one of those filaments, the two halves in- 

 stantly clasp together and interlock. Small prisoners 

 thus caged may still escape, but if the prey be large 

 and worth digesting, the leaves tighten, the glands 

 secrete more fluid, and the victim is slowly suffocated 

 and absorbed as before. 



The sun-dew and fly-trap possess considerable dis- 

 criminative power. Water and dry leaves dropped 

 on them are unnoticed; pebbles and such like are 

 rejected ; but meat, white of egg, and nitrogenous 

 substances are quickly seized and assimilated. 



Although thus possessing the functions of the lowest 

 animals these bloodthirsty insectivora are still vegetals. 

 They have roots, stems, leaves, and absorb nourish- 

 ment in the usual way ; but they are epicures, and 

 having acquired a taste for flesh indulge it to the full. 



(8) The most curious and in some ways the most 

 highly developed of the vegetals are the Protophyta, 

 a half-vegetal, half-animal organism, which constitutes 

 the " missing link " between plants and animals. We 

 shall only notice the more curious of the order. 



(a) Bacteria. — Dr Bastian alleges that a bacterium 

 can, at the will of the experimenter, be resolved either 

 into a vegetal or an animal, according as its conditions 

 of existence are prepared* In some cases an addition 

 of more non-metallic elements, or more light and heat, 



* Beginnings of Life, vol. i ; . pp. 214-235. 



