220 PROCEEDINGS OF THE NATIONAL MUSEUM vol. m 



Later, this material was taken to the North Carolina Department 

 of Agriculture Soil Testing Laboratory. There, through the kindness 

 of Dr. J. W. Fitts, both the food cell and the surrounding red clay 

 were analyzed for the amount of readily oxidizable organic matter 

 contained. A modified Walkley Black procedure was used (the major 

 chemical components being sulphuric acid and sodium dichromate). 

 This method oxidizes about 90 percent (by weight of soil) of the 

 organic matter. The siu-rounding red clay contained 0.64 percent 

 organic matter, while the larval food cell contained 7.60 percent. 

 This, according to Dr. Fitts, was very high, the usual surface soU in 

 the immediate area containing only 1 to 1.5 percent oxidizable humus. 

 From this it would appear that, if the adult beetle did not concentrate 

 the surface humus, it at least bm-rowed in spots with an extremely 

 high surface concentration. 



On July 1, 1952, the cage northwest of Raleigh was revisited. 

 On this occasion a quantity of water was taken along and the ground 

 in the cage kept thoroughly soaked. This made the digging of the 

 one located Bolboceras burrow considerably easier. At a depth of 7 

 to 8 inches a female liebecki was taken in the burrow. Seven inches 

 farther, at a depth of 14 inches, a fully grown third-stage larva was 

 taken at the bottom of the burrow, which for IK inches was packed 

 with humus and sand. Above this was a plug of red clay. The 

 burrow was a single tube, much like that diagrammed for Bolboceras 

 darlingtoni (Wallis) (pi. 10, fig. 1). The larva, slightly injured by 

 the trowel, was immediately preserved. No other adults or larvae 

 of liebecki were taken in the cage. 



It was interesting and fortunate for purposes of identification that 

 both adults remained in the biu-rows containing the larval cells. 

 Whether the presence of the adults in the biu-rows indicated any brood 

 care was not ascertained. This and many other questions concerning 

 the life history of liebecki still are unanswered. 



The subsequent description of the larva of Bolboceras liebecki was 

 based on the following material: One second-stage larva collected at 

 Raleigh, N, C, on June 19, 1952, by H. Howden, reared to third 

 instar; and one third-stage larva collected at Raleigh, N. C, July 1, 

 1952, by H. and A. Howden. 



Larvae of liebecki differed from Ritcher's (1947, p. 13) description 

 of simi in the following respects: Maximum width of head capsule 2.2 

 to 2.5 mm.; frons on each side with 2 or 3 posterior frontal setae, 2 

 setae in each anterior angle, 1 or 2 exterior frontal setae and 4 or 5 

 anterior frontal setae; labrum, antennae (pi. 6, fig. 3), and mandibles 

 similar to simi; maxilla differing only by having 4 or 5 setae, absent in 

 simi, on the base of the galea ; hypopharynx slightly asymmetrical with 

 oncyli separated by triangular structure (pi. 6, fig. 11); glossa emar- 



