INSECTS INJURIOUS TO THE PEAR TREE. 



Explanation. — Psylla Pyri — a, pupa, showing the under side ; b, upper side of same 



THE PEAR FLEA-LOUSE. 



{Psylla Pyri, Linn ? ) 

 Order of HOMOPTERA. Family of PSYLLID^. 



Whilst visiting the fruit farm of Mr. Parker Earle, of South Pas8, on 

 the first of June, my attention was called to the sickly condition of some 

 of his young pear trees, apparently caused by a leakage of sap from the 

 axils of the leaves; in some instances running down the branches and 

 trunk to the ground. 



Mr. Earle had exarrined his trees a number of times for the purpose 

 of discovering the cause of this mischief, but on account, as it after- 

 wards appeared, of the very small size and concealed position of the 

 real culprit, he had failed to detect it. Upon turning my attention 

 particularly to the points from which the flow of sap seemed to origi- 

 nate, and with the aid of a pocket lens, I discovered, imbedded in the 

 axils of the leaf-stalks, and immersed in the exuding sap, from one to 

 half a dozen minute, louse like insects, which were evidently the cause 

 of the injury. I afterwards captured a few of the mature or winged 

 insects which furnished the clue to their name and character. They 

 belong to the Homopterous Genus Psylla of Geoffroy, and are very 

 similar to, if not identical with a species equally injurious to the pear 

 tree in Europe, to which Linnaeus gave the name of Chermes Pyri. 



