84 ENTOMOLOGICAL SOCIETY 
Mr. Lugger referred to a statement by Dr. Hamilton, in the 
CanacttanJZntomologist (vol. xix, 1887, p. 64), in regard to the 
habit of Clceotus aphodioides. Dr. Hamilton found these beetles 
in cavities in the bark of a small dead tree, in which the bark had 
not yet become separated from the wood. Dr. Hamilton thought 
these beetles had sought the old burrows of some other wood- 
boring beetle to hibernate. Mr. Lugger said that he had fre- 
quently bred these beetles from their eggs, and had also found 
them in all stages in situ, viz., under the bark of dead trees, 
where they found food in the decaying material. It is very 
likely that the specimens found by Dr. Hamilton did not enter 
these holes to hibernate, but rather had made them to leave the 
place of their birth. 
JUNE 2, 1887. 
Nine persons present. President Howard in the chair. 
Mr. Smith gave in brief the characters of a new Arctiid genus, 
which he proposes to call Cerathosia. The only species, C. tri- 
color, has the appearance of a Lithosiid, but is Arctiid in char- 
acter.* 
Dr. Marx spoke on the Arachnid fauna of the District of Co- 
lumbia. He is preparing a list of the local fauna, and possesses 
already about 200 species found in the vicinity of Washington. 
Dr. Riley mentioned the peculiar fact that, in some instances, 
where trees have been enfeebled from other causes, spiders can 
prove quite injurious to them. Young elms in his grounds, re- 
cently transplanted, had been covered with spider-webs to such 
an extent as to prevent normal growth, and the spiders showed a 
great predilection for such in comparison with vigorous trees. 
Mr. Luebeck, of Philadelphia, spoke on the habits of Diccelus 
dilatatus. The beetle feeds, like the genus Cychrus, upon snails. 
In a number of instances he found the Dicalus with the head in- 
serted in the shells of Helix alternata, eating the enclosed snail. 
Dr. Riley exhibited various specimens, and made remarks 
thereon as follows : 
*The new genus has been more fully described by Mr. Smith in Ento- 
mol. Amer., iii, p. 79. 
