102 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



ciation, 1874), though he somewhat qualifies his conclusion by 

 the statement " That this process, which is comparable to 

 digestion, is not wholly due to the fluid first 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 the pitchers and put in glass tubes." Within a 

 short space of time a number of researches were made which 

 seemed to place the digestive capacity of Nepenthes beyond 

 doubt. Dr. Lawson Tait stated in " Nature " for 1875, that he 

 had succeeded in obtaining a substance resembling pepsin from 

 the liquid collected from the pitchers of various species of 

 Nepenthes. In 1876, a Paper was published (" Ber. deut. chem. 

 Ges.") by von Gorup-Besanez, in which he states that shreds of 

 blood-fibrin placed in the acid liquid (from N. phyllamphora and 

 gracilis) at a temperature of 40° C, were more or less completely 

 dissolved within an hour, and that the resulting liquid gave the 

 characteristic " biuret-reaction " indicative of the presence of 

 peptones. In the following year I published a Paper on the 

 subject in the "Journal of the Linnean Society" (Vol. xv., 

 1877), in which I showed that it is possible to prepare a glycerin- 

 extract of the pitchers, which, on the addition of acid, has a 

 well-marked digestive action on proteids. 



Moreover, the structure of the internal surface of the pitcher, 

 contrasting, as it does, strongly with that of Sarracenia, is such 

 as to suggest a digestive function. In Nepenthes, speaking 

 generally, honey-glands are borne on the under surface of the 

 lid, or about the orifice of the pitcher ; for a considerable, 

 though varying, distance from the orifice, the surface is smooth 

 and slippery ; and the remainder of the surface is provided with 

 glands which pour out the secretion : there is no region bearing 

 detentive hairs as in Sarracenia. Clearly the object in view is to 

 cause the insects to fall into the liquid filling the base of the 

 pitcher ; and the fact that the liquid is undoubtedly secreted 

 points to the conclusion that its object is not merely to drown 

 the insects, but to digest them as well. 



Nevertheless, the digestive capacity of Nepenthes has been 

 disputed of late years. Thus Dubois (" Comptes Rendus," cxi., 

 1H<)0) concludes that u the liquid contains no digestive juice 

 comparable to pepsin, and that Nepenthes is not a carnivorous 

 plant" ; and further u that the phenomena of disintegration or 



