37S NATURAL HISTORY OF AQUATIC INSECTS en. 



endeavoured to cleanse its comb with the tarsus of 

 the middle leg, but went about it in a very clumsy 

 fashion. 



" I was then satisfied that the comb is really used 

 to cleanse the antennae. I next endeavoured to find 

 out how Beetles which have similar habits but no 

 comb cleanse their antennae. It would 

 take too long to relate all the experi- 

 ments which I have made, but to be 

 brief, they do what is necessary by 

 the help of the spines on the tarsus 

 (Carabus), or those on the tibia or 

 tarsus (Notiophilus, Leistus, and 

 Nebria), or by rubbing the antennae 

 against plants and other objects 

 (Elaphrus). The operation often takes 

 up a considerable time where no 

 comb can be employed." 



Aepus is often found among small 

 molluscs (Rissoa, Lasaea) and is be- 

 lieved to prey upon them. Another 

 little Carabid, Cillenum or Bembi- 

 dium laterale, can often be seen in 

 thousands upon refuse washed up 

 by the tide. It is regularly submerged. 



The family of Staphylinid^e (Rove-beetles) in- 

 cludes several marine species. Bledius is common on 

 sandy shores near high-water mark. There are fif- 

 teen British species. They prefer a smooth expanse 

 of sand thinly coated with mud, and here throw up 

 little hillocks, half an inch or so in height. Hundreds 

 of these hillocks form one colony. On sandy shores 



Fig. 1 1 6.— Part of 

 fore leg of Aepus, 

 with comb upon 

 tibia. 



