June, 1915.] Fish-feeding Coleoptera of Cedar Point. 
527 
than fish remaining on the beach. For a period of six weeks a 
number of “traps” made by covering several fish with boards 
were maintained at different places on the Point, and kept in 
continual operation by frequently adding fresh supplies of fish. 
Other traps similar in structure were moved from place to place 
every few days. It was found that location had much to do with 
the number of individuals present, and that the traps maintained 
in regions of the deepest shade were most productive. Within 
certain limits the number of individuals and species increased with 
the age of the trap. In these traps larval forms of the families, 
Silphidae, Staphy-linidae and Dermestidae were frequent. In the 
aggregate members of the Histeridae were represented in larger 
numbers as adults than any other family, but their larvae were 
never present. 
During the early morning of July 25th, while making a trip 
along the beach two carp were found, weighing about two pounds 
each, not more than fifty feet apart, that had just been cast up 
by the waves Over one a box 14”xl8" was turned, protecting 
the fish from the sun and the birds. The afternoon of the 28th 
the box was removed and the sand for a radius of two feet from 
the fish and to a depth of about a foot was carefully sifted and the 
astonishing number of 1310 adult Hister beetles, practically all 
of them Saprinus pennsylvanicus Payk were taken. Most of 
these we found a few inches under the fish in the sand made wet 
with the juices. Accompanying these were nine adult Dermestes 
caninus Germ. To these might be added the five beetles taken 
from the stomach of a small toad found under the box buried in 
the sand. Only one of the five, however, was a fish feeder, it 
being Saprinus pennsylvanicus. Hundreds of Dipteron larvae 
were present, but not the slightest trace of beetle larvae save one 
of Trox scabrosus. 
The sand around the unprotected fish of some size and kind, 
already mentioned, was sifted but the result was the same as that 
found at other unprotected fish examined at different times. 
Of the beetles found at such times the Histers predominated in 
numbers with an occasional member of the Staphylinidae and one 
or two larval forms of Trox scabrosus. No other larval forms 
of coleoptera were found, the fly larvae were always found in large 
number. The total number of beetles found in these unprotected 
fish never exceeded 100 and averaged about 50. 
Some writers suggest that the Hister beetles instead of being 
carrion feeders may be predaceous, feeding on the larvae of flies 
universally present in carrion. Several experiments in which 
adult Histers were confined with fly larvae for several days with 
and without other food failed to show one case where a fly larva 
sacrificed its life to the Hister beetles. On July 31st, however, 
the writer saw two adults of Silpha americana eating fly larvae 
