. Bulletin of the Department of Agriculture. Agriculture. THE GEEElf JUNE BEETLE. 33 hoppers, the function of mating and egg laying by the beetles might continue normally in spite of their being parasitized. A Digger-wasp Enemy. Among the known natural enemies of the green June beetle, if we except such birds as robins and blackbirds, is one that is more than probably responsible for the extreme fluctuations in the numbers of this species observed in some years and in certain localities. During the months of August and September of the last decade of the nineteenth century, on numerous oc
. Bulletin of the Department of Agriculture. Agriculture. THE GEEElf JUNE BEETLE. 33 hoppers, the function of mating and egg laying by the beetles might continue normally in spite of their being parasitized. A Digger-wasp Enemy. Among the known natural enemies of the green June beetle, if we except such birds as robins and blackbirds, is one that is more than probably responsible for the extreme fluctuations in the numbers of this species observed in some years and in certain localities. During the months of August and September of the last decade of the nineteenth century, on numerous occasions the flight of a digger wasp, Discolia dubia Say (fig. 6), was observed by the senior author. The wasps gradually increased in numbers until they became suffi- ciently abundant to attract general attention. The same abundance. Fig. 6.—The digger wasp (Discolin diihia) : a. Female wasp; b, antenna of male ; e, cacoon showing opening above. Twice natural size. was reported in other quarters in the city of Washington, and it was presumed that white grubs of some sort were the attraction. Finally it was learned that the insect seemed to be present only in the male sex. Later the species was reared from Cotinis nitida in different localities and reported to the Bureau of Entomology. In Maryland, near Washington, the same phenomenon was wit- nessed, and it was also noted that the wasps congregated in great numbers on convenient shrubbery. It may be said in general that the wasp is most conspicuous on lawns and near shrubbery in just such localities as are frequented by its host. One year this species Avas so abundant in some of the smaller parks of Washington and so disturbed the children who used the parks for playgrounds that the wasp became the subject of newspaper notice. A few Avords in regard to the digger wasp above mentioned maj^ be interesting. It is one of our medium-sized species, measuring 186606°—22—Bull. 891 3. Please note that these images are extracted f
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectagriculture, bookyear
