12 DEPARTMENT BULLETIN 1267, U. S. DEPT. OF AGRICULTURE 
may be toxic for them. This view is supported by results of field 
observations, which show that larve of this species are only very 
exceptionally associated with manure. Thus in the old pasture at 
Tappahannock, where the larve were abundant, they were never 
found beneath the droppings of cattle, although repeated search was 
made for them in such locations. Furthermore, they were no more 
frequent in fields that had been treated with manure than in those 
that had been left untreated. The junior writer has repeatedly 
searched for the larve in fields to which manure had been added 
earlier in the season, but although the larve of certain other scara- 
baeids, such as Ligyrus gibbosus (De G.), Dyscinetus trachypygus 
(Burm.), and Cotinis nitida (L.), were unusually common in such 
fields, those of Huetheola rugiceps were either entirely lacking or 
extremely scarce. 
Whether, under natural conditions, the larve ever subsist upon 
living plant material is a question which can not as yet be answered. 
From the fact that the older larve in the breeding experiments were 
fed with kernels of corn, it would not be unreasonable to suppose 
that they may feed to some extent upon living plant material. The 
frequent association of the larve with grasses of the genus Paspalum 
suggests the possibility that they may feed upon the rootlets of these 
plants, though it is also possible that this association is purely acci- 
dental—a result of the parent beetles depositing their eggs in such 
spots while feeding upon the plants. 
Howard (7) and Titus (73) have inferred that the larve feed 
upon the dead and dying roots of the kinds of cultivated plants— 
sugar cane and corn—destroyed by the adult beetles. Titus, indeed, 
goes so far as to offer the suggestion that the object of the beetles in 
attacking sugar cane is less to secure food than to provide a supply 
of dead and decaying vegetation for the larve to feed upon. So far 
as corn is concerned, however, there can be little doubt that the 
beetles attack it primarily for food, and that if the destruction caused 
thereby is of benefit to the larvee it must be a very indirect benefit. 
The junior writer has tested the capacity of the very young larve to 
feed upon dead and decaying corn rootlets, and, while the experi- 
ments were not sufficiently extensive to settle the matter fully, the 
results were entirely negative. 
It has been suggested that the larvee may feed in decaying wood, 
as do those of some of the near allies of this species. Examination 
of old logs and stumps at Tappahannock for larve of Euetheola 
yielded only negative results, and it seems reasonably certain that 
they do not occur in such situations. 
In the experiments at Charlottesville an effort was made to rear 
the larvee from forest leaf-mold, but, although they appeared to eat 
this, only a very small proportion of the larvee tested lived beyond 
the earliest stages. There is no evidence that the larve ever feed 
upon such material under natural conditions. All attempts to find 
the species in timbered areas were unsuccessful. It is apparently 
limited to open situations. 
GROWTH 
The larva on hatching from the egg is approximately 3 muilh- 
meters long; when fully grown the length is about 32 millimeters 
(14 inches). Growth is rapid, the larva attaining full size in from 
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