Ninth Report of the State Entomologist 317 



not appear from Mr. Weed's report that the hibernating individuals 



were killed by this method. He states: 



Our present crop of cabbage was put into the field early in March^ 

 and at the same time a row of radishes was planted through the middle 

 of the patch. The radishes were well grown by the time the second 

 brood of bugs [the first spring brood] had hatched, and nearly all the 

 insects found their way to the radishes, where they were killed by 

 spraying with kerosene. At this date, June 15, hardly a single bug is 

 to be found in this patch, while cabbage planted in other parts of the 

 grounds are badly infested. {Bulletin N^o. 21 of the Mississippi 

 Agricultural Experiment Station^ June, 1892.) 



Unless there should be no survivors of the radish feeders which 



might transmit, through heredity, an especial fondness for that plant 



to their successors, it would seem to be desirable that only mustard, 



if equally attractive, should be used as a bait. We have no knowledge 



that M. histrionica has been reported as a radish pest, although long 



known to feed on it and on other Crucifer^e, but another member of the 



genus, probably M. niunda Stal, has recently appeared in that role, in 



California {Insect Life, iv, 1891, p. 83). 



Psylla pyricola (Foerster). 



The Pear- Tree Psylla. 



(Ord. Hemiptera : Subord. Homoptera : Fam. Psylltd e.) 



Foerster .- in Verhandl. d. naturh. ver. d, preuss. Rheinlande, v. 1848, p. 77 



Harris: Treat. Ins. New Engl., 1852, pp. 201-204; Ins. Inj. Veg., 1862, pp 



231-234 (early observations, habits, description, etc.). 

 Fitch: in Trans. N. Y. St. Agricul. See, xvi, 1856, p. 353; 3d-5th Repts. Ins 



N. Y., 1859, p. 35 (brief mention). 

 Uhler : in Rept. Commis. Patents for 1860. 1861, p. 314 (discovered in U. S.) 

 Packard : Guide Study Ins. , 1869, p. 53 (mention) ; Entomol. Begin. , 1888, p 



82 (mention). 

 Walsh-Riley : in Amer. Entomol., i, 1869, p. 225 (mention, in Eastern States) 

 LeBaron : 2d Rept. Ins. 111. , 1872, pp. 134-136, figures (injuries in Illinois). 

 Glover ; in Rept. Commis. Agr. for 1876. 1877, pp. 33, 34, fig. 36 (description 



locahties, etc.). 

 Thomas : in 7th Rept. Ins. 111., 1878, p. 73, fig. 12 (mention); in 8th Rept. do. 



1879, p. ]3, fig. 2, pp. 16-17 (general account, remedies, etc.). 

 Barnard : in Proc. Amer. Assoc. Adv. Sci., xxviii, 1880, pp. 478-486, plate 



(as P. pyrisuga). 

 AsHMEAD : in Canad. Entomol., xiii, 1881, p. 220 (questions KoUar's account of 



habits). 

 Riley : in Proc. Amer. Assoc. Adv. Sci., xxxii, 1884, p. 319 (mention); in Proc. 



Biolog. Soc. Wash., 1884, p. 69 (referred to pyricola oi Foerster); in 



Insect Life, v, 1892, p. 103 (synonym). 

 Loew : in Neue Beitrage, zur Kenntniss der PsylUden-Verh. Wien Zool.-Bot.» 



GeselL, xxxvi, 1886, p. 154. 

 COMSTOCK : Introduc. Entomol., 1888, p. 171 (brief reference). 

 Saunders : Ins. Inj. Fruits, 1889, pp. 145, 146, figs. 151, 152. 



