CONTRACTILE FILAMEMTS OF AGARICUS MUSCARIA. 77 



the part which remains after the resin has been removed by 

 alcohol is capable of swelling in water, and is the cause of the 

 movements. He supposes that the resin is intimately blended 

 with the water-absorbing substance. As far as my observations 

 go on Agaricus, they confirm the view that the filaments consist 

 of two parts, one soluble, the other insoluble in alcohol. 



If, instead of a water-absorbing substance, we substitute 

 living matter intimately blended with the resin, the above 

 description agrees with my idea of the constitution of a teasel 

 filament, viz. a large quantity of resin, animated by a small 

 quantity of living or irritable matter. 



From the small number of observations which I had time to 

 make on the Agaricus, I am not able to bring forward all the 

 arguments which convinced me that the flaments of Dipsacus are 

 protoplasmic. 



The one fact that such weak solutions as -y^ per cent, of 

 sulphate of quinine and camphor produce contraction seems to 

 me far morem favour of the view that the filaments of the Agaric 

 are protoplasmic than of the contrary belief. From the strong 

 similarity between the filaments of the teasel and the Agaric, it is 

 impossible not to give some weight to experiments performed on 

 the teasel alone, although such aj)plication of their results may 

 not be strictly correct. If it were proved that the movements of 

 the Agaric filaments were an imbibition phenomenon, I should be 

 quite ready to grant that the same is almost certainly true of 

 Dipsacus. The two cases must sink or swim together. 



As to what the physiological meaning of the filaments in the 

 Agaric may be I can form no conjecture. I have tried to show that 

 the filaments of theDipsacus are a resinous protoplasmic secretion; 

 whether the filaments of the Agaric are in any way homologous 

 to a secretion I cannot pretend to say. Professor De Bary to 

 whom I addressed a question on this subject was so kind as to 

 inform me by letter that probably the resinous matter results 

 from the disorganisation of the compact tissue which in the 

 young state fills up the space between the stalk and the lamellae ; 



by Beneke ("Studieu liber Vorkommen, &c., der Galletibestandtheil, &c." 

 Giessen, 1862), certainly resemble those of the teasel or Ai^aric to a certain 

 extent. One difference between these filaments and those of Dipsacus or 

 Agaricus is that they are not affected by weak reagents (Virchow, in ' V.'s 

 Arcliiv,' 1854, p. 562). Beneke states (' Arcliiv fiir Wiss. Heilkunde,' 

 1865, p. 380) that weak acids do not hinder the movement, but actually 

 causes the production of good lorms. This is quite different from the 

 behaviour of teasel filaments. When it is a question of strong solutions, 

 Beneke finds (' Studieu,' &c.) that acids retard while alkalies promote the 

 movement. This certainly agrees with the behaviour of teasel filaments. 

 On the other hand, it partially agrees with the behaviour of undoubted 

 protoplasm. De Barry describes (' Mycetozoen,' p. 50) the chmiges of 

 form produced by alkaline solutions in the plasmodia of the Mycetozoa. 



