132 THE WATER CABINET, 
in the section Pentamera, in which the tarsi of all the 
feet are five-jointed, the fourth being of ordinary size. 
The Dytiscus is a true water-beetle, being aquatic in 
both its larva and perfect forms. The larva, known as 
the water-tiger, is found in plenty in the muddy ditches 
round London, and is a strong, stubborn, ugly, and 
ravenous worm, with a tail formed for respiration, and 
DYTISCUS AND LARVA (REDUCED). 
curved mandibles to tear its prey to pieces. It is very 
active, and may be kept without difficulty ; but nothing 
else should be placed in the same jar, unless intended as 
food for this savage. A small fish thrown is eagerly 
clutched, and held firm by the claws; and the larva then 
plunges its mandibles into it, and is soon buried head- 
deep in the mangled body of its prey. I have generally 
fed them on beef, but they prefer small fish, or larva of 
