Insects Bred from American Larch 97 
having been devoured by the predator. Most usually the 
opening through the hard outer shell is through the posterior 
abdomen, this apparently being the most vulnerable point 
of attack. In one instance on opening the burrow a larva 
of P. dislocatus was discovered with its head thrust into the 
body of a recently dead P. rufipennis as far as the prothorax. 
When the clerid larva was removed the body of the scolytid 
showed fresh signs of having been eaten. There is also good 
evidence to show that both larvee and adults feed quite readily 
on the dead and dried bodies of scolytids and even upon those 
which must be well along in decay. Thus this clerid acts as 
a scavenger as well as a predator. 
The scolytids with which P. dislocatus have been found 
constantly associated in larch are Polygraphus rufipennis, 
Dendroctonus simplex, Eccoptogaster piceew and Crypturgus 
pusillus. It was actually taken from under the bark among 
the burrows of each of these scolytids and there can be little 
doubt that it acts in the capacity of a predator and scavenger 
in the burrows of all of these forms. It is believed that as 
a predator P. dislocatus (and other clerids) most often 
attack the adults rather than the larvee of scolytids. The 
larva or adult of the predator in order to reach the scolytid 
._larva would either have to construct a new burrow of its own 
through the bark or would have to clear the larval burrow 
of frass and enlarge it. On the other hand the adults are 
quite accessible. When in the brood-burrow, the predator 
ean reach them readily through the entrance to the nuptial 
chamber, while the young adults for a considerable time 
before emergence are readily accessible through the “ ventila- 
tion openings ” in their feeding galleries. 
Cymatodera bicolor Say. 
Cymatodera bicolor was described from a specimen from 
Arkansas and Horn (1888, p. 224) gives its range as “‘ The 
Middle and Gulf States.” It has later been reported by 
Wickham (1895, p. 249) from Ontario and Quebec, by 
Smith (1909, p. 802) from New Jersey, by Leng (1908, 
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