1887.] Prof. C. Ewart on Bacteria in Lymph , &c., of Fish. 267 
able. The fact that even when the bacteria have extended into 
numerous lymphatics, and even into the substance of the muscles 
surrounding the body-cavity before they are found in appreciable 
numbers in the blood, seem to indicate that the blood is most 
active in destroying bacteria. Again, seeing that although, when 
bacteria exist in considerable numbers in the inner layers of the 
myotomes of the trunk, they are often entirely absent (as proved by 
cultivations) from the outer layers of the same myotomes, it may 
be inferred that the muscles also have considerable power in pre- 
venting the spread of bacteria. Prom the observations made it 
appears that bacteria travel easiest along the lymphatic canals and 
spaces — the lymph cells being apparently less able to arrest their 
progress than the blood corpuscles. 
As to the nature of the bacilli found in fish nothing has hitherto 
been determined. Olivier and Richet seemed to think they are 
neither specific nor putrefactive. At first I thought they were 
putrefactive, but not specific. Having made some further experi- 
ments, I am now inclined to consider them specific, and not putre- 
factive. I was led to believe they were putrefactive, because I 
found the characteristic long delicate bacilli of the body-cavity in 
immense numbers between the mascular fasciculi of fish in which 
putrefaction had already set in. A perch, e.g ., which died having 
the body-cavity and the blood well charged with bacilli, was placed 
in a chamber with the temperature at 38° C. Fifteen hours afterwards 
the mascular bundles, even near the root of the tail, were almost 
completely enveloped with bacilli identical to those in the body- 
cavity, the bacilli filling up the inter-muscular spaces, and forming 
large irregular patches around the bundles. In this fish, twenty-four 
hours after death, micrococci and bacteria were extremely few in 
number, but before the fish had been forty-eight hours in the warm 
chamber the bacilli had largely disappeared, and, in their place, 
busily engaged breaking up the mascular fibres, first into fdaments 
and then into small short segments, were numerous small 
bacteria and micrococci. A trout, which contained bacilli in 
nearly all the tissues during life, was placed in a solution of 
phenol (5 per cent.) sufficiently long to destroy the organisms in 
and around the fish (the intestine having previously been removed) 
without reaching those in the muscles, and then transferred into 
