612 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
bus and made careful notes for me. It is found boring partly in the 
solid wood in all stages. 80 numerous were the insects that the pattern 
of the larval burrow, which is usually very characteristic in the Scoly- 
tids, was confused and undecipherable. The insect is very destructive 
to the tree by hastening decay, although it was not observed to at- 
tack perfectly healthy trees. The adolescent states show little that is 
speciticially characteristic, the larva having the uoruial form and lack- 
ing legs. 
This insect has a persistent enemy in a small predaceous beetle (Clerus 
ichneumoneus) which attacks and destroys the Scolytid when the latter 
emerges from its gallery and the larva of which, there is every reason 
to believe, also destroys the Scolytid larva. 
The following additional Coleoptera are also known to affect Celtis, 
but are not peculiar to it, the most injurious being No. 20: 
CERAMBYCIDiE. 
17. Mallodon melanopus Linn. 
18. Mallodon serrulatus Lee. 
19. Smodicum cucujiforme Say. 
20. Romaleum atomarium Drury. 
21. Liopus crassulus Lee. 
22. Ataxia crypta Say. 
Scolytid m. 
23. Micracis rudis Lee. 
24. Scolytus muticus Say. 
25. Phloeotribus frontalis Oliv. 
The following species of Cucujidae are found under the decaying 
bark: 
26. Catafjcnus rufus Fabr. 
27. Scalidia linearis Lee. 
28. Ino reclusa Lee. 
29. Lamiophlceus hornii Casey. 
Cecidomyidous Hackberry Galls. 
The Cecidomyidous galls occurring on twigs and leaves of Celtis 
often assume a close resemblance to those produced by the Psyllids and 
are almost as numerous in species as the latter. They have not yet 
been thoroughly studied, and a full description is not here intended, nor 
a characterization of the insects which make them and which are very 
difficult to rear. But a short account of a few of the more striking galls 
which are liable to be mistaken for those made by Psyllids will be ap- 
propriate. 
30. Cecidomyidous galls on the tender twigs, either singly or placed 
in rows of two or more specimens ; occurring also singly on the petiole 
or on the lower surface of the leaf. Gall usually resembling somewhat 
