21. 
22. 
23. 
24, 
232 
Larvae forming centipedelike engravings on the inner 
bark, killing the trees. Young adults feeding on the 
small twigs of living hickory 
Scolytus quadrispinosus 
In the inner bark of decadent or felled elms: 
Making short, simple, longitudinal egg galleries; 
young adults injuring small twigs in feeding 
Scolytus multistriatus, S. mala 
Making branched, transverse galleries; young adults 
often hibernating in bark of healthy elms 
Hylurgopinus rufipes 
Breeding in the inner bark of decadent and felled ash; 
making regular, transverse, branched engravings 
Leperisinus aculeatus, L. fasciatus 
Breeding in the trunk and larger branches of decadent or 
felled birch, beech, sweet gum, and wild cherry; ir- 
regular radiate galleries in the inner bark 
Dryocoetes betulae 
Engraving the inner bark and sapwood of decadent and 
felled mulberry; adults hibernating in inner bark of 
livine® treesin...... Ne ee Phloeotribus frontalis 
Breeding in the inner bark of injured wild plum and wild 
cherry: 
In short, unbranched, longitudinal galleries 
Scolytus rugulosus 
In forked, transverse galleries 
Phloeotribus liminaris, P. mississippiensis 
In the thin bark of sumac trunks 
Pityophthorus rhois, P. crinalis, P. scriptor 
Breeding in the smaller limbs and twigs of hickory: 
Short, unbranched burrows in the smaller limbs 
Chramesus hicoriae 
Very slender, branched, longitudinal burrows in twigs 
Cryptulocleptus dislocatus 
Breeding in the small branches of hackberry: 
Unbranched, longitudinal galleries 
Scolytus muticus, Chramesus chapuisit 
Transverse branched galleries 
Phloeotribus dentifrons 
Breeding in the small branches of oaks and chestnut 
Pseudothysanoes lecontei, Pseudopityophthorus spp. 
Breeding in the small branches of basswood 
Pseudothysanoes rigidus 
Breeding in the small branches of redbud 
Pityophthorus natalis 
Breeding in the small branches of sweet gum 
Pityophthorus liquidambarus 
In the bark, wood, or pith of small branches and twigs 
Of various hardwoods 0...0. 4 Hypothenemus spp. 
Unstained pinhole burrows in the W00d ooo... 
Stained pinhole burrows extending into the wood .......... 
Very small pinholes in the living twigs of pines, extend- 
ing through the wood to the pith and continued there 
as egg galleries; entrance covered by pitch tube: 
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