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Again insects may be found with four membranous transparent wings, as 

 dragon flies (order Pseudoneuroptera) or cicadas (order Hemiptera), but in these 

 orders the wings have a great number of nervures, or veins, forming a close net- 

 work, and in all hemipterous species (bugs) the mouth is transformed into a pro- 

 boscis, and lacks the mandibles or jaws common to Hymenoptera, and which are 

 very apparent in large species like the bees. 



We are informed that the abdomen of the female is furnished with a saw 

 ovipositor, a borer, or a sting, and the order can be roughly divided into three 

 sections based upon these differences in the sexual organs. The first section may 

 be styled Phyllophaga (leaf -feeders), and contains the well-known saw flies, the 

 larv86 of which are caterpillar-like and possessed of feet. The second section 

 includes the Xylophaga (wood-feeders), generally known as horntails, the larvae 

 of which infest the trunks of trees, and the Parasitica (parasites) to which belong 

 the long-stings and numerous allied forms. The third section Aculeata (sting- 

 bearers) contains the bees, wasps, ants, etc. 



Of the first and third sections as above indicated I have in former reports 

 treated briefly, and I will now endeavor to outline the Parasitica, which consti- 

 tute almost the entire second section, and which by reason of their great number 

 and complexity of structure will make my task a difficult one to undertake in a 

 single paper. 



The section Parasitica contains at least half of the described species of our 

 Hymenoptera, and the number of undeseribed forms must be very large, as many 

 of them are extremely minute and require more careful collecting and study than 

 many entomologists can devote to them. They are divided into several families, 

 of which some contain a large number of genera and species, and which will be 

 briefly treated of in systematic order. 



Cynipid^. — This family coii tains a moderate number of small species (often 

 minute) and is divided into two sections, one containing three and the other two 

 subfamilies. The species contained in the first section are in the larval state 

 chiefly producers of galls, or dwellers therein, instead of being truly parasitic in 

 their mode of life. There is reason to believe, however, that the few species 

 which constitute the first subfamily (Ibaliinse) are true parasites upon the larvae 

 of wood-boring insects. The principal Canadian species is lhalia macwlipennis 

 Hald., which occurs somewhat rarely on maple and beech. The structure of the 

 insect is such as to attract attention, for though of moderate size (hardly three- 

 fourths of an inch in length) it is still the largest of our Cynipidae, and is easily 

 distinguished by its strongly compressed or knife-shaped abdomen. Within the 

 abdomen, which constitutes merely a sheath for it, is coiled a delicate ovipositor, 

 much longer than the insect itself, with which it deposits its eggs in the decaying 

 trunks of the beech and maple, where the larvae when hatched probably exist 

 upon other insects infesting the wood. 



The subfamily Cynipinse contains species producing galls upon plants. The 

 trees most subject to their attacks are the various species of oak ; the galls occur- 

 ring upon them and the insects produced therefrom being in themselves a suffi- 

 cient study for an entomologist. Some of the galls, such as the oak-apple, are of 

 enormous size as compared with the minute grub which occupies the central cell 

 therein, and which by some mysterious influence upon the growth of the plant 

 sk-ucture causes this wonderful abnormal development. The various species of 

 roses are also very liable to the attack of these insects, the galls chiefly occurring 

 being large potato-shaped ones upon the roots, oval woody enlargements of the 

 stems and clusters of pea-shaped swellings upon the leaves. Although various 

 plants, including the raspberry and blackberry, are subject to these attacks there 

 is not space to enumerate them here. 

 5 (en.) 



