442 Dr. J. C. Ewart. On Rigor Mortis in Fish, [June 16, 



into the muscles, and the rigor was passing from the remainder of 

 the middle third and making its appearance in the front portion 

 of the posterior third. At 6 p.m. the rigor had all but gone from 

 the middle third, and a weak rigor had set in in the posterior 

 third. At 8 p.m. (82 hours after death) the whole eel was quite 

 limp — the rigor on the posterior third having been weak and of short 

 duration. The alkaline reaction increased from before backwards, to 

 about 3 inches from the tip of the tail, where it was neutral, and 

 bacteria could be detected in the muscles a little beyond the middle 

 half. Next morning (29th March) all the muscles were alkaline, and 

 a few bacteria were present even in the muscles near the tail end, 

 and the anterior portion was smelling slightly. This eel was under 

 observation until the 13th April, when putrefaction had considerably 

 advanced. While under observation the eel was kept in water which 

 varied from 48 — 52° F. I may add that the blood and peritoneal 

 fluid were examined immediately after death, and that though small 

 bacilli were fairly abundant in the lymph, it was impossible to dis- 

 cover any organisms in the blood. In this eel the muscular irritability 

 lasted in some of the muscles for nearly eighty-two hours after death. 

 As a contrast to this above experiment, I may describe shortly 

 another. 



(3.) On the 6th April, an eel, also about 18 inches in length, which 

 was killed by an electrical shock from a Holtz machine, passed imme- 

 diately into rigor — what might be called " cataleptic rigor." The 

 posterior half — in which there is no body-cavity — was sterilised (by 

 placing it for a short time in a 5 per cent, solution of phenol) and 

 then introduced with the usual antiseptic precautions into a jar of 

 sterilised distilled water. The rigor still (June 16th) continues on 

 this portion (the posterior half) of the eel, while the anterior half, 

 which was introduced into a 5 per cent, solution of phenol after the 

 rigor had disappeared, is now quite limp and soft. 



From these experiments it may be inferred that under ordinary 

 conditions there is an intimate relation between loss of irritability 

 and the setting in of rigor, and that rigor vanishes as the bacteria 

 invade the tissues. 



3. The Time at which Rigor appears. 



Under ordinary circumstances the setting in of rigor in the various 

 kinds of fish seems to depend on the amount of irritability of the 

 muscles at death. In all probability it might be possible to dis- 

 cover when the rigor would come on by determining the amount 

 of free acid in the muscles ; in other words, there is a relation 

 between the appearance of the rigor and the amount of catabolic 

 material in the muscles at death. This seems to vary in an unac- 

 countable way ; e.g., if three two-year-old trout of as nearly as 



