Dragon flies are widely distributed over the world, but are most plentiful in the warmer zones; about 2,000 have been described from all parts of the world, of which 107 species are recorded from Australia; but as Billinghurst was able to collect 41 species in one circumscribed district in Victoria (Victorian Naturalist No. 1, 1900), systematic collecting would certainly add many more to our list. In the early stages of their life dragon flies are aquatic; the female deposits her eggs on the foliage of water plants, sometimes dipping into the water to be sure they are submerged. The slender larvae with wing pads in place of the future wings have somewhat the form of the adults, and are carnivorous, feeding upon all kinds of smaller water insects. The dragon flies form a very distinct division of the Neuroptera; every organ is beautifully adapted for their aerial life, their immense eyes giving them an outlook on all sides, while the slender cylindrical body does not impede their flight; and the great oar-shaped wings strengthened with many stout nervures enable them to twist and turn in the air with wonderful ease and rapidity. The LIBELLULIDAE are thick-bodied dragon flies of medium size, and comprise a number of fine species. The larvae are short broad creatures with wide heads; they live in the mud on the bottom of ponds. _Rhyothemus graphiptera_ belongs to a genus containing over 30 species ranging from Africa to China, and the Eastern Archipelago to the New Hebrides. It measures 2½ inches across the wings, which are yellowish brown, beautifully mottled with darker tints; the front pair are blotched at the base, a slender stripe in front running into the first of 2 irregular transverse bands about the centre and tip; in the hind pair the two apical bands have basal markings consisting of three small irregular blotches: it is found in the northern parts of N.S. Wales. [Illustration: =Fig. 31.=--Diagram of a Dragon Fly. _a_, antenna; _ar_, arculus; _b.s_, basilar space; _c_, costal nervure; _s.c_, sub-costal nervure; _e_, eye; _f_, front; _m_, median nervure (or radius); _s.m_, sub-median; _m.s_, median sector; _m_, membranule; _n_, nodus; _n.s_, nodal sector; _o_, occiput; _p_, pterostigma; _p.s_, principal sector; _s.s_, short sector; _s.t_, sector of triangle; _t_, triangle; _i.a_, inferior appendage; _s.a_, superior; _a.n_, antenodals. The numerals refer to the segments of the abdomen. (Original R. J. Tillyard.)]