ON iROTllUSlON OF TKOTOFLASMIC FILAMENTS. 203 



liave the same effect as nitrogenous or aramoniacal solutions, I 

 cannot say. These salts produce aggregation in Drosera and 

 in this way they again resemble ammonia in action. 



It will be sten from the above account that the effect of infu- 

 sions of meat is to cause an enormous and probably abnormal 

 production of filaments which usually free themselves from their 

 attachment. In some cases the filaments are very transparent, 

 like those produced by ammoniacal solutions; in other cases they 

 do not differ in refractive index from the ordinary filaments, 

 which are usually bright and highly refracting. In the latter 

 case the filaments resemble those shown in figs. 8, 9, and 15; 

 m fig. 15 are represented the raj)id movements of a free and 

 unattached filament. The change from fig. 8 to fig. 9 took 

 place in about half an hour ; the curiously beaded filament 

 in fig. 8 had doubtless originally issued from the trichome as a 

 simple whip-like body. The aberrant forms produced by slow 

 contraction are exemplified in fig. 12, for in this case also there 

 is little doubt that the mass was originally a simple filament. 

 I am, unfortunately, unable to say to what cause this latter kind of 

 movement is due. I have seen curiously shaped or actively 

 moving filaments in fresh specimens mounted in distilled water; 

 this seems to negative the view that the changes in question are 

 due to the absorption of nitrogenous matter. But it must be 

 remembered that a transverse section of a young leaf mounted 

 in water is practically exposed to a nitrogenous fluid owhig to 

 the death of the protoplasm killed in the young leaf-cells in 

 making the sections. I can only re{)eat that these changes do 

 under some unknown conditions certainly occur, and that some- 

 what similar changes are certainly brought about by immersion 

 iu infusions of meat and solutions of carbonate of ammonia. 



Nature and physiological relations of the filaments. — 1 have 

 now given some account of the physiological behaviour of these 

 remarkable filaments. Before proceeding further it will be well to 

 attempt the discussion of the question, what relation does the 

 power of protruding filaments bear to other processes of vege- 

 table physiology ? When I first observed the filaments I found 

 it extremely difficult to believe that they were protoplasmic organs 

 issuing from the glands. I was even inclined to suspect that 

 they might be parasitic organisms of some unknown kind which 

 merely fixed themselves on the summits of the trichomes to avail 

 themselves of the putrescent fluid retained by the connate leaves 

 of the plant. Such facts as those given in one of Mr. Dallinger's 

 memoirs,^ should make one cautious in rejecting such a theory, 

 nevertheless I believe it may certainly be dismissed. It is impos- 



' " Practical Notes on Ileterogenesis," 'Popular Science Review,' Oct., 

 1S76. 



