Sia : VICTOR E. SHELFORD 
females of C. limbalis. Very many holes were made in the fresh, 
clean sand, but eggs were laid in only afew of them. These holes 
in the fresh sand have frequently been opened and found to be 
without eggs. Why fresh, clean sand should be so attractive 
to the females and fail to satisfy the final act of egg-laying is 
strange. Pure humus appears to be avoided -when either moist 
or dry. 
During the experiments, the different kinds of soil werekept 
as nearly equally moistened as possible, but a slight depression was 
provided in each. These were wetter and were especially selected 
by the females when standing water was not present. Eggs are 
not laid in dry or very wet soil. Moisture is evidently an 
important factor in controlling the egg-laying. I have found the 
beetles copulating and depositing eggs in my cages, on damp, 
cloudy days. This has not been observed in the case of most 
other species. It would appear, then, that light is not very im- 
portant. However, as in the case of C. limbalis, deficiency or 
excess 1n one factor is sufficient to cause the soil to be avoided or 
only little used. 
5. Geographic distribution. The habitat relations of C. tran- 
quebarica are less definite than those of C. limbalis. We have 
found it on the bare clay of the overflow flats of the Arkansas 
River at Dodge City, Kansas, depending on stream moisture; on a 
path at the top of a terminal moraine at Waverly, New York, de- 
pending on climatic moisture; on alluvium along the Des Plaines 
River at Lyons, Illinois; and on the residual and alluvial soils of 
various parts of Colorado, New Mexico, Nevada and Idaho. In 
nearly all these localities, the soils examined were similar in their 
moisture content. The species is always nearer water courses in 
the more arid climates. The only place in which the soil mois- 
ture was deficient about the burrows was at Las Vegas, Nevada, 
at the height of the dry season. This is a region of winter rain, 
where the soil would be much moister in spring, the egg-laying 
season of the species. The larvae were much nearer the water 
(Las Vegas Wash) than I have found them in the moister 
climates. The bottoms of the burrows were nearly as moist as we 
commonly find them near Chicago. 
