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to those unacquainted with their economy. The Ichneumonidae are 

 hynienopterous insects, i.e. having transparent wings, varying much 

 in size, and serve as a useful check on those caterpillars which 

 prove destructive to vegetation. The female has three bristles at 

 the end of her long, slender body, the middle one of which is a 

 tube, called by entomologists an ovipositor, by means of, and 

 through which, the egg is transmitted; the two lateral ones merely 

 serving as a protection to it. This ovipositor varies much in length 

 ■ — in those species which pierce the insect itself it is short, whilst in 

 those which deposit their eggs in the nests of other insects it is 

 remarkably long. Their mode of proceeding is as follows : when a 

 caterpillar is found the female fly alights on it, and with a jerk 

 drives its ovipositor into its body, somewhere near the head, and 

 deposits its egg; it then withdraws the ovipositor and flies away. 

 This does" not in any way interfere with the caterpillar, it still 

 feeds on as before, until it arrives at the chrysalis stage, by which 

 time the egg of the ichneumon is hatched to a small white maggot; 

 it then begins eating that fat part of the caterpillar which surrounds 

 the alimentary canal, always avoiding those parts which are essen- 

 tial to life, aware apparently that the death of the caterpillar would 

 also cause its own destruction ; by and bye it becomes a chrysalis, 

 and soon after the perfect insect or imago. There are upwards of 

 a thousand species of these insects already described; and it is pos- 

 sible, 'says Newman in his " History of Insects," page 7 (to which 

 we refer our readers for a more detailed account of this interesting 

 tribe), " that every butterfly and every moth, indeed almost every 

 insect, has one peculiar to itself. The history of them all is nearly 

 similar. ,, 



On the high Yarra banks, near the Lunatic Asylum, we may find 

 the rare grass Cinna ovata, and the coarse Anthistiria Australia 

 (kangaroo grass)— abundantly too Nicotiana suaveolens with white 

 flowers ; Muehlenbeckia complexa (Polygoneas) is trailing along the 

 banks, and around some of the acacias climbs a beautiful Billar* 

 diera with long pendulous yellow flowers. The tea trees of the 

 colony, Melaleuca gunniana and Leptospermum, are now in bloom ; 

 and several varieties of the Helichrysum. (everlasting) ornament the 

 dry stony banks with their rich orange-coloured flowers. As we 



