310 Report of the Department of Entomology of the 



triangular form, or one wound running into another. The more 

 seriously injured pears would be rendered unfit for sale from their 

 knotted surface, even if after such a drain upon them they should 

 continue upon the tree, which is not at all probable. 



"The insects taken upon the injured fruit were the tarnished plant- 

 bug (Lygus lineolaris (pratensis L.). Although they were not actually 

 observed feeding upon the juices, there can be no reasonable doubt 

 of their being the authors of the injury. This form of attack upon 

 the fruit has not been previously recorded, yet their fondness for the 

 blossoms of the pear is known, and they are also known to be destruc- 

 tive to the fruit of the strawberry." In this attack the insect appeared 

 to exhibit a preference for the fruit of the variety Angouleme, while 

 Anjou and other varieties seemed to be exempt from injuries. 



In 1888 Mr. Barry 2 of the foregoing firm observed newly-set 

 pears that were severely attacked by casebearers (Coleophora sp.) 

 The injury consisted of numerous small holes in the surface of the 

 fruit which caused them to become gnarled. The detection of this 

 attack was considered by Lintner as the explanation of many of the 

 scars and unsightly deformations of apples and pears which hereto- 

 fore he had not been able to refer to any known insect. In July of 

 the same year pears similarly scarred were received by him from 

 Mr. J. F. Rose of South Byron. 3 The injuries were described 

 as follows: "Some of the spots retained their original round form, 

 while others had become elongated, triangular, lozenge-shaped or of 

 irregular forms as a result of the growth of the fruit. The margins 

 of the scars were blackened, elevated, and the somewhat enlarged 

 interior contained pale, yellowish, granulated matter. From twenty 

 to thirty of the scars occurred on each pear and several of the same 

 character on the stems." In an accompanying footnote a portion of 

 the injury was attributed to the plant-bug Lygus invitus Say. 



'Rept. Inj. Ins. N. Y. 7:347. 1890 (1891). 



9 In our correspondence with Mr. Rose we have learned that in 1891 he actually 

 conducted a series of experiments for Lintner to determine the species of 

 insect responsible for knotty pears. As the petals were dropping from the 

 young fruits he covered a number of clusters of pears with very fine netting, 

 and introduced into these cages some plant-bugs which were observed to be 

 very common on trees beginning to show deformed fruits. Pears attacked 

 by the confined insects showed injuries similar to those which he had observed 

 in his orchards during previous years. These " observations " on the 

 work of Lygus iniitus are apparently those mentioned by Lintner in his report 

 for 1891. 

 In 1895 the experiments were repeated by him for Slingerland with similar results. 



