30 A. COTTAM — OUE BEITISH BEETLES : 



useful little scavengers. Instinct impels them to buiy any dead 

 animal that they find, for the purpose of providing food for their 

 offspring. Having excavated the ground round the carcase, till 

 it gradually sinks below the surface, the female lays her eggs 

 in it, and the grubs when hatched feed on the dead body, 

 which by being buried is preserved much longer than if it had 

 been left on the surface. Another common species in this section 

 is the " bacon-beetle " {Dermestes lardarius). 



Among the water-beetles included in this section is one often 

 known as the "harmless water-beetle" {^Hydrous piceus), and 

 therefore in some demand for aquaria. It is by no means the only 

 harmless water-beetle, as none of the Palpicornes are predaceous. 

 But this one is so conspicuous — it is the largest of all our British 

 beetles, the only one that comes near it in size being the "stag- 

 beetle " — that it is really a striking creature in an aquarium, 

 especially as the water magnifies it and makes it look larger even 

 than it really is. 



4. The Lamellicoenes. 



We now come to the Lamellicornes or chafers. In this section 

 the structure of the antennse is (as in the Clavicornes, Palpicornes, 

 and Longicornes) the character from which the name is derived. 

 The club of the antenna3 in this section is formed of lamellae or 

 plates, something like the leaves of a book, varying from three to 

 seven in number, and in some of the genera movable. Every 

 species in this section may be at once known by this peculiarity of 

 structure. "Why they should be called " chafers " I do not know. 



The British species are not numerous — under 90 ; but many of 

 them are common, some among the commonest of our beetles, and 

 in consequence, a larger number have English names than in any 

 other section. The most common of all is perhaps the " cockchafer " 

 {Ilelohntha vulgaris). This insect in some years is excessively 

 abundant, and great damage is then done to meadows, the grub 

 feeding in the roots of the grass. In this species the antennae of 

 the male have seven and those of the female six plates. The 

 smaller "summer chafer" [Rhizotrogus sohtitialis) has only three 

 plates to the club of the antennae. 



In the eastern and south-eastern counties of England two species 

 of Lamellicornes are common that are hardly found elsewhere in 

 this country. The "June bug" {Phyllopertha horticola), a small 

 chafer with a green thorax, is one of these, and the "stag-beetle" 

 {Lucanus Cerrus) is another. This large beetle (with the exception 

 of the large water-beetle before mentioned), our largest indigenous 

 species, has acquired its English name from the enormous develop- 

 ment of the mandibles in the male. In the female they are much 

 smaller. I have two specimens of the male taken in Watford. 



One of our commonest chafers is the " clock " or " dumble-dor " 

 {Geotrupes stercorarius). There are half a dozen species of the 

 genus, and two or three are common. One or other of them may 

 be seen flying at dusk, or walking slowly on the ground by day, 



