The Proteolytic Enzyme of Nepenthes. 
BY 
S. H. VINES. 
HE first indication of the possession by the liquid 
JL secreted by the pitchers of Nepenthes of the power 
of digesting proteids was afforded by the observations of 
Sir Joseph Hooker 1 , who found that ‘after twenty-four hours’ 
immersion the edges of cubes of white of egg are eaten 
away and the surfaces gelatinized ; fragments of meat are 
rapidly reduced ; and pieces of fibrin weighing several grains 
dissolve and totally disappear in two or three days.’ He 
does not, however, go so far as to refer the digestive action 
altogether to the secreted liquid : on the contrary, he says, 
‘that this process, which is comparable to digestion, is not 
wholly due to the fluid secreted by the glands, appears to 
me most probable ; for I find that very little action takes 
place in any of the substances placed in the fluid drawn from 
pitchers and put into glass tubes.’ At the same time he 
does not state what other agency he assumes to have been 
operative in the process of digestion or disintegration, though 
it would appear from the context that probably he had the 
action of Bacteria in view. It is important to note that he 
distinctly recognizes an antiseptic action of the liquid, and 
that he draws attention to changes taking place in the glands 
1 Address, Brit. Association, 1874; see also Nature, X, 
[Annals of Botany, Vol. XI. No. XLIV. December, 1897.] 
