PATHOLOGY. 141 



.muscle, and many of them were entirely disintegrated, as was evident from the 

 remnants of the muscular fibres and the granular material which took their place 

 between the interstices of the connective tissue. This granular material was seen 

 throughout the specimen, some of it being of a brown tint, and probably repre- 

 senting disintegrated blood corpuscles. The internal organs were all in a state of 

 atrophy, more particularly so the liver, the tissues of which under the microscope 

 bore a striking resemblance to acute yellow atrophy. The serous sacks were all 

 largely distended by blood stained serum. The heart muscle was also in a condi- 

 tion of atrophy, its chambers empty, and the blood dark and not coagulable. 

 Blood examined microscopically showed appearances to be mentioned shortly. 



The Effects of certain Venoms on the Coagulability of the Blood. — One of the most 

 interesting differences in the action of the venoms of the Rattlesnake and Cobra 

 and which was pointed out some years ago by more than one observer, is that 

 the former venom partially or completely destroys the coagulability of the blood, 

 while the venom of the Cobra has no such marked effect. The blood of animals 

 poisoned with Crotalus venom is usually thin and dark, the clots form slowly, and 

 are very soft and easily broken up. 



Some direct studies were made to test more accurately this interesting property 

 of the Crotalus venom, and it was thus observed that it is not peculiar to the 

 poison of this genus, but is also a characteristic of the Moccasin. Several of these 

 observations which were made with the venom of the Crotalus adamanteus we 

 record in detail. 



Experiment. — Five test-tubes were used : — 



No. 1 empty. 



No. 2 contained ^ grain dried venom dissolved in 0.5 c. c. distilled water. 



No. 3 " i " " in 1.0 " 



No. 4 " \ " " in 1.0 " 



No. 5 " 2 drops glycerine solution of venom, equal parts. 



These test-tubes were packed in snow, to retard coagulation and to give the venom 

 a better opportunity to act, the tubes remaining in this condition for about half an 

 hour. The main artery in the leg of a large etherized rooster was exposed, and a 

 canula placed in it. The blood was allowed to flow into the tubes in the order 

 of their numbers, the tubes being gently shaken to mix the venom and blood. The 

 operation began at 3:55 and ended at 4:00 P. M. At 4:35 the tubes were ex- 

 amined. The blood in No. 1, which contained no venom, was firmly clotted, in all 

 the others the blood was fluid. At 4:55 the test-tubes were all taken from the 

 snow. Blood in No. 1 was firmly clotted and of a bright-red color ; blood in Nos. 

 2, 3, and 4 was fluid and venous in appearance ; blood in No. 5 was fluid and 

 of a brighter red than No. 1. The tubes were then corked with raw cotton and 

 set aside. 



Twenty-four hours later blood in No. 1 was firmly clotted, in Nos. 2 and 3 tarry, 

 in No. 4 tarry, but thinner than in Nos. 2 and 3, in No. 5 perfectly fluid ; in the 

 lower half of the tube was a mass of corpuscles, while the upper half had the appear- 

 ance of pure serum. 



Forty-eight hours — no appreciable alteration. 



