THE APPLE-LEAF BUCCULATKIX : PARASITES AND PSOCID.E. ICl 



Described from many female specimens ; male, unknown. Parasitic upon 

 Bucculatrijc. pomifoUella Clem. 



Mr. Howard also informs me that ia examining a bottle of alcoholic 

 specimens of the above species in Professor Riley's collection, he had 

 found a number of examples of a Chalcid which he thouirht might be 

 also parasitic upon BitcculatrixpomifolicUa, or a secondary parasite. The 

 material was in too poor condition for determination and description. 

 One specimen of a Braconid had also been found in the collection, 

 marked "parasitic upon Bucculatrix pomifoUella.'^ 



Psocus Bred from Bucculatrix Cocoons. 



Two specimens of i'.so6'«.^' were also received by me from Professor 

 Eiley, which he had bred from the Bucculatrix. They were sent to 

 Dr. Hagen for determination, and were found by him to be identical 

 with Psocus semistriatus Walsh {P roc. Acad. Nat. Sci. Phila., 18G2, 

 p."361), as compared with types in the Museum received from Mr. Walsh. 

 Possibly, P. seniislriatus may prove to be the same as P. qiiictus, 

 which had been previously described by Dr. Hagen from an example 

 from the State of New York and another from Georgia (see Proc. 

 Ent. Soc. Phila., 1863, p. 167). 



It is probable that this Psocus is not a true parasite upon the Buc- 

 culatrix, but is associated with it as a scavenger, feeding upon the 

 exuvia of the larva. Dr. Hagen has written me as follows of these 

 Psocina : "No Orthopteron nor Pseudoneuropteron has been observed 

 to live as jiarasites, and I think that they are not parasitic. But cer- 

 tain species prefer to live as inquiline^, and one species was described 

 by Linnaeus, more than a century ago, as Hymenopteron. Some spe- 

 cies of CcBciliiis and Blipsocus live here and in Europe in willow and 

 oak galls. Two species were brought from Brazil by Mr. B. P. IMann, 

 which he considered as parasites of the coffee-leaf miner. Such Psoci 

 like to feed on cast skins; and, perhaps in the case of Psocus semi- 

 striatus, on the dry skins of the Bucculatrix caterpillar, as my expe- 

 rience has shown me the fondness of many Psoci for larval skins." 



The PsocidcB are a low form of insects constituting a family in 

 the division of Pseudoneuroptera. They are small forms, measur- 

 ing in length from 1 mm. to 8 mm.: Psocus venosus, our largest spe- 

 cies, which lives on apple and maple trees, has an expanse of wings of 

 from 12 mm. to 15 mm. (about 0.5 to 0.6 in.). They occur in both the 

 winged and wingless states, and somewhat resemble plant-lice in gene- 

 ral appearance. The larger number feed on dry vegetable substances 

 and lichens. They are quite common, and may be often found con- 

 gregated in large companies on trunks of deciduous trees and among 

 the herbage of some, of the evergreens ; they also frequently occur in 

 houses. Atropos divinatorius (0. Fabr.), originally described from 

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