Zoology.'] NATURAL HISTORY OF VICTORIA. [Insects. 



usually more distinct in the male than in the female, is sometimes 

 almost absent or reduced to a small discal spot and a trace of the 

 stripe at the apex of the wing in male specimens. The front and 

 sides of the thorax also vary, for, although usually whitish in the 

 male and brownish in the female, the two sexes are sometimes alike 

 in this respect from the longer spatulate white scales or hairs being 

 more or less abundant ; and similarly the edges of the abdominal 

 segments are usually browner or less distinctly margined with 

 white in the female than in the male, but both sexes vary con- 

 siderably in this respect. 



My late friend Mr. Walker, in his Catalogue of the British 

 Museum Heterocera, suggests that the Eudoxyla d'Urvillei 

 (Herr.-Sch.) is only the female of this species, and I can see no 

 difference in the figure ; but as the different locality of Tonga 

 Tabu is given for it, I hesitate to combine the species. 



The moths of the family Hepialidce are popularly known as 

 "Swifts" or "Swift-moths," from the great quickness of their direct 

 flight in the dusky twilight. The group is divided into three sec- 

 tions, typified by, 1st, the Hepialus, the true Swifts or Ghost- 

 moths ; 2nd, by Cossus, or the Goat-moths ; and, 3rd, by Zeuzera, 

 or the Wood-leopard-moths, as they are popularly called, respec- 

 tively. They all have a complex neuration of the wings, which 

 are deflexed when at rest. The larvae of all are thick fleshy naked 

 grubs, with a few hairs ; they have 6 pectoral, 8 ventral, and 2 

 anal feet ; and have the prothorax protected by a broad horny 

 shield ; often spending three years in the larva state. Those of 

 the first group inhabiting subterranean burrows and feeding on the 

 roots of grasses ; those of the other two feeding on the interior of 

 the wood of timber trees, to which they prove very destructive 

 from boring great vertical canals, so weakening the tree that it 

 either dies or is blown over. In most forest- bearing countries the 

 natural enemy of these larvae and protector of the trees from their 

 destructive action is the group of Birds of the family Picidce or 

 Woodpeckers, who by instinct know where the larvae are, and by 

 the powerful strokes of their suitable bills cut down quickly on 

 the larvae through the sound wood, and, transfixing the grub with 

 their long worm-like barbed tongue, draw it out, and devour it. 



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