NORTH AMERICAN GEOTRUPINAE — ^HOWDEN 219 



was again placed in use, this time for Geotrupes hornii. After the 

 specimens were put in the cage a quantity of dead leaves and cow 

 dung was added and the screen top was securely fastened. During 

 the time that the cage had not been in use the soil (red clay) had 

 become firmly compacted and, except for a rich layer of finely divided 

 surface hmnus, had approximately the same profUe as the neighbor- 

 ing undisturbed ground. 



On Jime 19, 1952, I was digging in the cage for the hornii when 

 an unarmed male liebecki was unearthed at a depth of 6 inches. The 

 specimen was in a straight vertical burrow that continued downward 

 mto the subsoil, which began at a depth of 6 or 7 inches. The burrow 

 was followed downward with difficulty. The rather dry, compact, 

 red clay soil had to be chipped away, after a time bending the tip of 

 one trowel so badly that a second one had to be used. Sim previously 

 had also noted the propensity of liebecki to dig in fii'mly compacted 

 soils in New Jersey. Wallis (1928, p. 123) quotes from correspondence 

 with Sim as follows: 



Now in the liebecki localities the soil is pretty purely clay with numerous 

 pebbles and rock fragments . . . [at] Jenny Jump Mountains in North Jersey the 

 stones are so numerous that a burrow may be very irregular in its downward 

 course. Too, the clay is more firm and difficult to dig [through]. So as I recall 

 them the beetles were found from one inch to six or eight inches down. 



WhUe the Raleigh clay lacked the numerous pebbles, it was certainly 

 difficult to dig through. 



The liebecki burrow continued without turns to a depth of 11 

 inches. There it turned slightly and, behmd a half-inch plug of red 

 clay, it was packed with a mixture of some sand grains and rich, very 

 fine surface humus. In the center of the cell of humus was a second- 

 stage larva, about 12 inches below ground level. The larva, with its 

 ceU, was placed alive in a metal salve box. At least one other Bol- 

 boceras burrow was noted in the cage, but digging was temporarily 

 postponed because of the difficulties that the excavation of the burrow 

 entailed. 



The larva in the salve box increased rather rapidly in size, sifting 

 through the sand for the humus. Often a grain of sand, coated with 

 humus, was grasped and rotated between the mandibles and maxillae, 

 and then discarded minus its coating. On June 26, 1952, the larva 

 was noted to be a third instar. On June 28, 1952, the larva died, 

 probably killed by unaccustomed high temperatures (over 90° F. in 

 the room in which the salve box was kept). The larva was imme- 

 diately preserved and the remaining unconsumed portion of its food 

 supply carefully saved. 



