216 BRITISH SERPENTS. 
noticed it was slightly affected with canker. It got 
rapidly worse, and died two or three weeks afterwards. 
I then cleaned out the vivarium with soap-and-water, 
and the next specimen I placed therein was a small 
specimen of the viperine snake (7'ropidonotus tugimanus). 
This snake was also quite healthy. About five weeks 
subsequently this snake became affected with the dis- 
ease, and after lingering for eight or nine weeks, died. 
This time I scrubbed out the vivarium with hot soda- 
and-water, and put in the vivarium a specimen of 
the English ring snake (7opidonotus natriz), which 
showed sign of canker a week afterwards. In this case 
the symptoms were very severe, the eyes becoming 
quite white and opaque, and the head very much en- 
larged in size. Death took place in a few days. I 
did not use that vivarium again for about six months, 
and then I enamelled it inside and out, and have not 
had the misfortune to lose any specimens since.” 
From this most interesting series of cases of canker 
it seems very evident that a serpent once infected 
with the disease may leave the germs in the cage or 
vivariuin it has been inhabiting, and I should stronely 
advise any one who loses a snake from canker to have 
the cage thoroughly disinfected with a strong solution 
of carbolic acid, repeating the washing at intervals of 
three days until it has been done three or four times! 
1 Mr Horton has sent me a leopard snake which was supposed to 
have died of canker. After careful examination, no sign of tuber- 
culosis could he found, only inflammatory changes being present, 
