The typical gall-fly deposits her eggs in the tissues of the selected plant by means of her ovipositor, which is beautifully adapted for the purpose; she injects in some cases a fluid that keeps the wound from closing up at once and so destroying the delicate egg. Most of the Cynips galls are rounded woody excrescences. The Gall Wasps have wings with few cells and no stigma; the front portion of the thorax is joined to the second; the ovipositor is concealed; the antennae straight, containing from 13 to 15 joints. I described three hymenopterons forming galls on wattles (Proc. Linn. Soc. N.S.W. 1892), but these insects submitted to Dr. Mayr some years afterwards proved to belong to another family. The only species described from Australia are 3 named by Ashmead (Pro. Linn. Soc. N.S.W. 1900), which were collected by Koebele without any exact locality being given; and _Hypodiranchis aphidis_ described by me as a parasite of the common peach aphis in the Agricultural Gazette N.S.W. 1904. Family 6. Parasitic Wasps. CHALCIDIDAE. This is a very extensive family, the members of which differ from the other small wasps in having the antennae elbowed, the first segment often as long as all the others combined; the antennae may be simple, but are often clubbed at the tips, and in the males of some groups with the segments or joints feathered or furnished with slender branching fingers. The delicate gauze-like wings are traversed by very few veins, and the abdomen is produced into all sorts of curious shapes, ornamented sometimes with remarkable anal appendages; and the ovipositor of the female, though often short, is sometimes much longer than the whole insect, and is usually prominent. These tiny little creatures deposit their eggs in the eggs, larvae, and pupae of other insects, wood galls, and excrescences produced by other insects, though a few groups are plant feeders and even produce galls. Most of them are very minute, and can only be collected by keeping infested galls, leaves, eggs and cocoons in jars and breeding them out, so that the majority of them escape the eye of the ordinary collector, though among the most beautiful of all insects in rich colours and delicate structure.