118 INSECTS AT HOME. 



Gryrini, except that, in the case of those insects, the eyes are 

 divided by a broad, fiat band, and in the present family by a 

 narrow ridge of horny substance. The body is very convex and 

 the thorax large, in order to give room for the muscles that 

 move the large wings and the powerful digging fore-legs. 

 Three genera of Geotrupidse exist in England, two of which 

 Avill be illustrated by examples. 



On Plate V. Fig. 3, niay be seen one of the commonest 

 English species, represented as crawling up the trunk of a 

 tree. This is the Geotrupes stercorarius, popularly known as 

 the Dor Beetle, the Flying Watchman, the Ddmble-dor, and 

 similar names, according to the locality in which it lives. The 

 genus Geotrupes has the basal joint of the antenna rather 

 long, and the fourth joint shorter than the fifth, the body very 

 convex, and the basal joint of the tarsus is the shortest. The 

 generic name Geotrupes is formed from two Greek words, 

 signifying ' earth-digger,' and, as we shall presently see, is a 

 very appropriate one. 



The colour of this species is black above, sometimes 

 glossed with green or blue, and i*ich shining-violet beneath. 

 On the middle of the clypeus there is a sharp tubercle. The 

 thorax is smooth, except at the margins, which are thickly 

 punctured, and on each side there is a nearly circidar im- 

 pression, tliickly punctured in the interior. The middle of the 

 scutellum is punctured, and the elytra are striated, the spaces 

 between the striai being smooth. The sexes may be distin- 

 guished by means of the tibiae of the first pair of legs and the 

 femora of the hind pair, the male having on the inner side of 

 the front tibia a single erect spine, and the inner edge of the 

 hind femora strongly toothed. As this insect is liable to much 

 variation in colour, it is necessary to call attention to these 

 minute points of stj-ucture by which the species can be definitely 

 ascertained. 



The life history of this Beetle may be briefly told as follows: — 



In the autumn evenings the Beetles may be seen flying 

 about in large circles, as if they were predacious insects quar- 

 tering the ground in search of prey. In one sense, this in- 

 exactly what they are doing, as they are hunting after a fa- 

 vourable spot wherein to place their eggs, and are wheeling over 

 the ground in hopes to find one. Attracted probably ^^y the scent, 



