274 



(April, 



able to find these recorded, albeit G. stercorarius is, T suppose, abundant in every 

 meadow. To observe properly the burrows and tunnels of G. stercorarius^ requires 

 the careful raising of considerable pieces of turf, a work of some labour, and not to 

 be regarded as beneficial to pasture land. 



Under a patch of cow or horse droppings, I frequently found a Qeotrupes, alone, 

 in a burrow of several inches in length ; but, whenever the carrying down of 

 pabulum and the deposition of ova were going on, there were invariably a male and 

 female beetle in the burrow. 



This buiTow extends nearly vertically downwards to a depth of from six to eight 

 or even twelve inches ; and as many as five or six pairs of beetles are sometimes 

 at work under one dropping. This vertical burrow is almost always made without 

 any excavation, simply by the thrusting of the earth aside as the beetle forces its 

 way down. It often happens that, when the mouth of the burrow is beneath the 

 centre of the dropping, this opening is kept free for the supply of pabulum, and a 

 subsidiary canal is carried along the surface of the ground from this point to the 

 edge of the dropping, where the removed earth is ejected. The cavities wherein 

 the eggs are laid branch horizontally from the bottom of this burrow in various 

 directions, and at slightly varying heights, to the number of six or eight, the lower 

 ones being made last. Each branch is about an inch wide, and four or five inches 

 long. The earth is removed from these tunnels, and forms the little heaps so con- 

 spicuous beside the droppings beneath which stecorarius is at work. Each of these 

 horizontal tunnels contains one egg, and a store of pabulum. The rounded further 

 end of the tunnel is firmly packed with concentric layers of dung. In the centre 

 of these is a cavity, half-an-inch deep, and three-eighths high. Its slightly hollowed 

 floor is semi-circular behind, and in front nearly straight. The arched roof descends 

 behind to the floor, and the front of the cavity is a perpendicular wall. This cavity 

 is carefully lined with, perhaps I ought rather to say is formed of, a layer of earth 

 worked to a clay-like consistence, and marked very often inside by the front tibia) 

 of the beetles, as if they had been used as trowels. 



The total capacity of the cavity would be sufficient to hold half-a-dozen eggs, 

 one only, however, lies loose on the floor j it is quite unsoiled by the earth, nor is 

 a loose particle of earth often to be found in the cavity. How the beetles close it 

 without allowing earth to fall in, I have been unable to devise any method of 

 observing ; it is done comparatively loosely, whereas, as I have mentioned above, 

 the dung previously arranged round the end of the tunnel is tightly packed, as is 

 also that which afterwards is packed, layer upon layer, into the remaining part of 

 the tunnel. The last half or three-quarters of an inch of the tunnel next the 

 pei-pcndicular burrow is filled, not with dung, but with earth. 



The egg is -j^^ of an inch in length, rather thicker at one end (where it is -j'u 

 inch in thickness, than at the other), and shghtly contracted in the middle ; it is 

 of pale straw colour, veiy delicate and easily broken. Before the young larva is 

 hatched, the egg increases slightly in length, and becomes of nearly double the 

 previous diameter, viz., about ^ inch. This appears to arise from imbibition of 

 fluid, and possibly also partly of air. 



These arrangements, so carefully made by Geotruj^es stercorarius^ arc turned to 

 their own benefit by A2^hodius jporcus. At or about the time the egg cavity is being 

 closed, the $ of A. 2>orcns arrives and makes her way into it, usually, I think, by 



