274 



ABSORPTION OF NrXRlMENT BY INSECTIVOROUS PLANTS. 



cones and evaporated water failed to reveal the slightest trace of 

 lithium. 



Series III. — Pinguicula litsitmiica. 



Locality. — The same as before. 



Method of experiment. — In the first series of experiments upon 

 this plant the method adopted was that of Series II. already described ; 

 but finding lithium in the roots, and also in the earth near them, the 

 results thus obtained seemed untrustworthy, and they were therefore 

 subjected to the same process as that employed in Series II. 



Results. — The results of the experiments confirm those obtained 

 by the first method, and are given in the Table : — 



Series III. — P. lusitanica. 

 Preparation. Examination. 



Remarks. — Comparatively few experiments have been made upon 

 these plants, as I have previously been unable to obtain them in 

 Bufiicient numbers : the above results are reliable. 



Conclusion. — In his work on Insectivorous Plants, Mr. Darwin 

 has proved the absorption by the tentacles on the leaves of the 

 Droseras and the hairs on the leaves of the Pinguiculas by observing 

 the aggregation of the protoplasm in the cells composing them, 

 and by the demonstration of the microscopical structure of the 

 stems and leaves. It is hoped, however, that the experiments already 

 described (which were mostly completed before I was aware of the 

 publication of this work) may still be not without value, as proving 

 conclusively that the products of digestion after absorption by the 

 leaves do enter the leaf-stalk, and are thence distributed to other 

 parts of the plants, 



♦ In both cases it was faint and at a considerable distance from the apices of 

 the cones apparently where the ends of the prepared leaves had rested upon 

 them. 



