WATEE-BBETLES. 211 



Acillii, have the first three joints of the anterior tarsi dilated. 

 The only species calling for mention here is H. transversalis. 

 The tipper part of the body of this beetle is black, the 

 margins of the thorax are a dull red, and those of the 

 elytra are yellow. The legs are also a dull red. This insect 

 is found in the ponds of different parts of England, and is 

 fairly common. 



We have in Britain nineteen species belonging to the 

 genus Agdbus, of which A. bipustulatus is one of the largest, 

 being nearly ^in. long. It is an active and handsome beetle, 

 and looks exceedingly well in the aquarium as it swims to 

 and fro, with a most conspicuous bubble of air attached to 

 the apex of its elytra, looking like a drop of quicksilver in 

 contrast to the blackness of the insect's body. Although 

 A. bipustulatus has a rather large appetite for its size, it is 

 not likely to do any harm in a general aquarium if it is 

 well fed. I saw very recently one of this species sharing 

 a worm with a small minnow, or rather the insect was attacking 

 the head of the worm while the fish was trying to swallow 

 the tail. This beetle is ovate in shape and black in colour. 

 There are two red spots upon the crown: hence the specific 

 name. The legs are a brownish black, and there are three 

 rows of punctm-es and quite a network of scratches upon 

 the elytra. A. bipustulatus is common almost everywhere, and 

 may be found at any season of the year. A. bipunctatus is 

 somewhat smaller than the last species. It is ovate and rather 

 flat in shape. The upper part of its body is yellowish, and 

 the under brownish-black. Upon the thorax there are two 

 round dark spots, whence the specific name. The legs and 

 the tip of the abdomen are a reddish colour. A. maculatus 

 is an active and prettily-marked beetle ; it is rather common, 

 but looks very well in the aquarium. The shape of the 

 insect is oval. The elytra, which are black, have pale-yellowish 

 spots, lines, and margins. The thorax is yeUow, with its 

 anterior and posterior margins black, and the legs are of a 

 reddish colour. The beetle is about iin. in length. 



Two of the three species belonging to the genus Laecophilus 

 are very common and very small. They are only about fin. in 



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