. The Cambridge natural history. Zoology. GALL-FLIES 523 After what we have said as to the mode of nutrition of parasites it will be understood that the physiological conditions of life may not be so different in a gall-dweller and a parasite as would at first be supposed; and it is perhaps not a matter for much surprise that good characters cannot be found to separate the gallicolous from the parasitic forms. Fam. I. Cynipidae—Gall-flies. lFi7)f/s with very few cells, ivith no darlc imtcli {stigma) on the anterior margin; pronotum fixed to the mesonotum, and at each side extending back to the
. The Cambridge natural history. Zoology. GALL-FLIES 523 After what we have said as to the mode of nutrition of parasites it will be understood that the physiological conditions of life may not be so different in a gall-dweller and a parasite as would at first be supposed; and it is perhaps not a matter for much surprise that good characters cannot be found to separate the gallicolous from the parasitic forms. Fam. I. Cynipidae—Gall-flies. lFi7)f/s with very few cells, ivith no darlc imtcli {stigma) on the anterior margin; pronotum fixed to the mesonotum, and at each side extending back to the point of insertion of the front iving. Ante7inae not elboived but straight, composed of a moderate number (li3-15) of joints. Early stages passed either in galls or as parctsites in the bodies of other Insects. The Cynipidae are always small, frequently minute, Insects; usually black or pitchy in colour. The simple struc- ture of the antennae and thenumber of their joints are of importance as an aid in identifying a Cynipid. The mesonotum is usually re- markably convex, and has, behind, a prominent scutel- lum, which more or less over- hangs the small metanotum and the median segment; these are perpendicular in their direction ; the sculpture of these posterior parts of the alitrunk is usually deep and remarkable. The abdomen has usually only a short petiole, so as to be pseudo- sessile ; but there are some genera in which this part is rather long. The abdomen is generally so very much changed in outer form that its structure is not easily understood. The visible por- tion is frequently in larger part made up of the greatly enlarged dorsal plate of the second or third segment, or of both. These large plates are really chiefly composed of free flaps, and on lift- ing them up the large ventral plates are disclosed, although these appeared previously to be nearly or quite absent. In the female. Fig. 346.—Neuroterus lentimlaris. Please note that these images are extr
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
