104 the ^dutfi AiistrAhan fiaturaiisi. 



A LARGE SOUTH AUSTRALIAN INSECT. 



(By Arthur M. Lea, F.E.8.) 



(Contribution from the South Australian Museum.) 



Our largest South Australian insect, or at least the one 

 that, with legs and wings extended covers the greatest space, 

 is undoubtedly the female of our beautiful walking-stick, or 

 leaf-insect, Tropidoderes childreni; it sometimes measures nine 

 inches in length, and the same in width, but the average is 

 about eight inches. In bulk of body and in weight, however, 

 it is exceeded by females of our large timber-moth, Zeuzera 

 affinis, and in other parts of Australia there are still larger 

 insects. 



Witli wings folded it appears of a uniform pale green, and 

 harmonises perfectly ^vith the eucalyptus foliage, amongst 

 which it moves, and upon which it feeds. The front wings are 

 rather small, green above, tinged with red below, and almost 

 of an even consistency; but each of the hind wings appears to 

 be in two parts, a front part like the front ones in thickness, 

 and a hind part that is much larger, thinner, and of a very 

 pale, shining green; the thicker part has a conspicuous red 

 patch near the base, and its under-surface is mostly red; there 

 is also a purple patch where the wing joins the body; the red 

 and purple are entirely concealed when the wings are folded. 

 The middle and hind legs, and the sides of the mesothorax (the 

 part of the body to which the front wings are attached) are 

 closely set Avith short spines or teeth, giving them a saw-like 

 appearance. 



The male differs from the female in being much smaller, 

 with longer and much thinner legs, longer antennae and 

 smaller wings, the front pair usually Avith a narrow whitish 

 stripe ; the tip of its abdomen is also without a canoe-shaped 

 appendage, that is very conspicuous in the female. 



Egg-laying begins soon after mating, and is continuous 

 during the life of the female, the eggs being simply allowed 

 to drop to the ground when ready; each egg is about the size 

 of a grain of wheat, and has a curious cap-like attachment at 

 one end ; the newly-hatched larva is of a very pale green, with 

 thin, spidery-looking legs; when nearing maturity four bud- 

 ding wings become evident, and later these change to the full 

 wings of maturity. 



The species can fly, but as with others of the family, sel- 

 dom does so, the female even less readily than the male. 



It occurs in Victoria and Western Australia, as well as in 

 our own State, and is eaten by magpies, crows, and other fairly 

 large birds; but the great reduction in its numbers as com- 

 j.Mi-ed with former years, is supposed to be due to the sparrow. 



