175 
esting tieM for .study and observation before any one who will make a 
thorough study of the two families that include these species. Let us 
see if more may not be known of the families before many seasons 
have passed. 
Mr. Sirrine remarked that Prof. Forbes lias found a Coccus on white 
clover which may be the same as the one mentioned by Mr. Davis. 
Mr. Ash mead exhibited specimens of a mealy-bug — probably Dacty- 
lopius destructor — which he found occurring abundantly on a plant 
(Cyperus alvernifolius) growing in the room in which the meetings were 
held. He thought it possible that the species described by Mr. Davis 
would prove to be the one characterized by Prof. Forbes as Coccus 
trifolii. 
Mr. Howard said that the theory hazarded by the author, viz. that 
Eriococeus azalece Comst. was introduced from Belgium on Azalea, was 
almost certainly incorrect, since the species is not known in Europe, 
while Prof. Comstock has recently found it on wild plants near Ithaca, 
indicating, with almost equal certainty, that it is a native species. 
He said also that the two old species of Dactylopius referred to by Mr. 
Davis have been shown by Beiiese to be both synonymous with Euro- 
pean species, and that the latter author has worked out their life 
history with great detail. 
Mr. Marlatt read the following paper: 
THE PEAR-TREE PSYLLA IN MARYLAND. 
By C. L. Marlatt. Washington. D. C. 
THE PSYLLA IN THE OKCHARD OF CAPT. ROBT. S. EMORY. 
About the middle of July of the present year the Department received 
information of an overwhelming invasion of the Pear-tree Psylla (P.sylla 
pyricola) in one of the largest pear orchards in Maryland, if not in the 
United States. The orchard in question belongs to Capt. Eobt. S. 
Emory, is located near Chestertown, Kent County, on Kent River, in 
the very heart of the famous u Eastern Shore" fruit district, and con- 
tains over 20, 000 pear trees. The success of Capt. Emory as a pear 
grower during the last thirty years has made him an authority on the 
subject, and he has manifested great intelligence and promptness in 
combatting all former attacks of disease and insect enemies. The pres- 
ent invasion, which is perhaps the worst which has occurred in his 
experience, he is preparing to combat with his customary energy, and. 
we hope, with his usual success. 
The pear-tree Psylla has not hitherto been reported south of New 
York, although extending westward as far as Michigan, and occurring 
