520 on the physiological action of casca bark. 



Action on Muscle. 



Effect on Structure of Muscular Tissue. 



The effect on fresh muscular tissue of immersion in casca 

 solution was carefully watched with an oc. 3 obj. 7 of Hart- 

 nack's microscope without any change in the structure being 

 discovered (Experiment XLYI). We then (Experiment XLVII, 

 March 22nd) examined the " naked-eye " and microscopical 

 changes produced in muscular tissue by prolonged immersion 

 in a watery solution of the alcoholic extract, the effect of 

 which solution in preventing the development of Bacteria has 

 already been detailed (p. 493). 



A. The solution in which the muscular tissue had been 

 placed presented, in addition to the absence of Bacteria, a few 

 noteworthy points ; it preserved its original slightly resinous 

 smell, and deposited a fine light-brown sediment, which, under 

 the microscope, appeared as a granular structureless detritus. 



B. The muscular tissue to the naked eye appeared hardly 

 altered in consistence : the fibrous sheath was firm ; there was 

 no smell. Under obj. 7 Hartnack the fibres were seen to be 

 very granular, in part only preserving their transverse striation ; 

 the general appearance closely resembled ordinary fatty degene- 

 ration. Some of the fibres were tlien soaked in ether for 24 hours ; 

 on examination after this the granulations had in great part 

 disappeared. Many of the fibres appeared to consist merely of 

 collapsed tubes of sarcolemma ; where they were not collapsed 

 they showed plain transverse striae. 



Six weeks later the muscle was again examined ; it having 

 remained in the same casca solution all the while, it was now 

 reduced to the condition of a rather tough gelatinous pulp ; the 

 sheath of the muscle retained its strength. Under the micro- 

 scope there was seen a mixture of granular and fibrous material, 

 with a large quantity of oil-globules and flat crystals, and when 

 treated with ether these were completely removed. 



