. Annual report - Entomological Society of Ontario. Entomological Society of Ontario; Insect pests; Insects. 71 ExODONTES.—This division is very poorly represented in Canada, or at least in collections. The species are small, but may be distinguished by an examination of the mouth parts ; the mandibles have the tips turned outward (as the name of division indicates), and cannot therefore be used for biting. Flexiventres.—This division con- tains species which differ from all the other braconids in having the segments of the abdomen freely articulated, so that it can be bent under the thorax. T
. Annual report - Entomological Society of Ontario. Entomological Society of Ontario; Insect pests; Insects. 71 ExODONTES.—This division is very poorly represented in Canada, or at least in collections. The species are small, but may be distinguished by an examination of the mouth parts ; the mandibles have the tips turned outward (as the name of division indicates), and cannot therefore be used for biting. Flexiventres.—This division con- tains species which differ from all the other braconids in having the segments of the abdomen freely articulated, so that it can be bent under the thorax. There is only one sub-family, the Aphid- iinse, and the species are very small, yet they are of great economic importance, as they are parasites of various species of aphides, or plant-lice. The larva feeds inside the aphis, which becomes swollen, and finally is found fixed to the plant on which it has been feeding, a mere dead shell from which the tiny parasitic fly has escaped. The grain aphis is said to be kept in check by one species, which alone must save an immense sum to our farmers. Fig. 37. —Here we have an- other very extensive family ; the species differing gi*eatly in structure and in habits. They are always small, but frequently are very brilliant in appearance, glittering with bright tints and metallic lustres. It will only be possible to glance at a few of the forms, as the great diversity of structure which obtains among them, and their minuteness make their study and identification difficult except for one who can devote much time to it. The wings have scarcely any traces of venation, except the vein along the front edge. Leucospis affinis is our largest species ; a black and yellow fly about one- fourth of an inch long, with its ovipositor curved up over the abdomen in a curious manner. It is frequently found on golden-rod, and is a parasite of Please note that these images are extracted from scanned page images that may have been digit
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectinsects, bookyear1872
