Zoology.'[ NATURAL HISTOKY OF VICTORIA. [Insects. 



Plate 40. 



THE CASE-MOTHS. 



The extraordinary insects figured on this plate are amongst the 

 most cm-ious and striking of the " common olyects " in Austraha, 

 meeting the eye everywhere, fi-om the abundance of the conspicuous 

 protecting sacks or cases which the larva? construct and carry about 

 with them, hanging to the trees in all directions, fixed by the 

 uppermost anterior end and swinging loose otherwise. In structure 

 of the female and in habit they are the most abnormal and singular 

 of all Lepidopterous Insects : the females being thick, smooth, 

 naked, fleshy, grub-like creatures, totally destitute of wings, and 

 having only minute rudimentary traces of legs, antennae, or eyes. 

 These apterous females never leave the sack or case in which they 

 dwelt while in the larva state, but after meeting the males at the 

 lower aperture of the case commence to bring forth the young in 

 myriads ; these escaping in crowds let themselves down each by a 

 silk thread spun from the lower lip until they reach a twig or leaf, 

 and then immediately begin to construct each a separate case of 

 tough silk and extraneous materials, such as particles of bark, &c., 

 to protect it during the period of its larval existence. These larval 

 sacks or cases are open at each end, the caterpillar coming suffi- 

 ciently out of the anterior aperture to use its three pairs of thoracic 

 legs for locomotion when feeding, usually fixing a part of the edge 

 of the aperture by fibres of silk temporarily to the twig it is on, so 

 that if alai'med it can suddenly withdraw completely within the 

 case, which then remains hanging with the apertures so completely 

 closed that, if the nature of the object was not known, it would 

 never be suspected to contain a vigorous voracious larva. A young 

 fi'iend, walking with me in Richmond Park the first evening I 

 an'ived in the colony, collected a number of these cases from the 



Dec. IV. [ 41 1 F 



