37 
were perpetually doing battle like knights of old, charging on each other 
most furiously, with the final result one morning of my finding both 
dead on the surface of the water, one of them having half swallowed 
the other, but the latter in the operation choked his conqueror, with 
the result mentioned. A subsequent specimen of mine was in the 
habit of secreting himself between two stones, with part of his body only 
exposed, as if watching everything. There is apparently much of the 
snake in their habits, and the same timidity exists in each. The least 
noise disturbs their equanimity and thunder seeme] particularly to affect 
my specimen. Although he occasionally moved round in the daytime, 
night was the time for his activity, and the artificial light of a room 
seemed in no way to interfere with his apparent recognition of time. 
One eel at a time affords ample opportunities for studying the habits of 
that family. 
One of the most interesting fish to watch, is the cat-fish, which I 
am seldom without, but it must be: kept well fed, and even then the fins 
and tails of the other fish hear evidence of its attacks upon them It is 
astonishing what an amount of food a cat-fish will swallow. You can 
watch his stomach swelling out to such an extent that it' presents the 
appearance of a fowl's crop when fed to repletion. After he has 
thoroughly bloated himself out, he generally settles down, under or beside 
a stone, and lies there in a sort of comatose state for some time, closely 
resembling in this the serpent family. As soon as the effects of his 
meal have passed off, he becomes one of the most restless of the 
occupants of the aquarium, and swims backward and forward and up 
and down, incessantly, as if calling attention to his wants. I have not 
the slightest doubt that, after a time, fish know intuitively to a certain 
extent, when feeding time comes and the party that feeds them. I think' 
that cat-fish are affected by, and feel coming changes of weather, but 
one cannot deduce conclusions from observations taken in a room where 
the temperature is probably uniform, as compared with the natural 
temperature out of doors. 
Sticklebacks I have had in abundance, but more' than two at a time 
become a nuisance. It is a perpetual warfare all round, especially if 
the males predominate. They, together with sun-fish, are, probably the 
most pugnacious of all fish, showing hostility even to my finger when 
