175 



esting field for study and observation before any one wlio will make a 

 thorougli 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 has found a Coccus on white 

 clover which may be the same as the one mentioned by Mr. Davis. 



Mr. Ashmead exhibited specimens of a mealy-bug' — probably Baety- 

 lopius destructor — which he found occurring abundantly on a plant 

 {Oyperus alvernifoUus) 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 

 UriococcHs azaleoe Comst. was introduced from Belgium on Azalea, was 

 almost certainly incorrect, since the species is not known in Europe, 

 while Prof. Comstock has recently foundit 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 Berlese 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, T). C. 

 THE PSYLLA IN THE ORCHARD 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 {Psylla 

 py'ricola) in one of the largest pear orchards in Maryland, if not in the 

 United States. The orchard in question belongs to Capt. Robt. S. 

 Emory, is located near Chestertown, Kent County, on Kent River, in 

 the very heart of the famous "Eastern Shore" fruit district, and con- 

 tains over L>0,0()0 pear trees. The suc(;ess 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 promj)tness 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 



