HORN KXl'EDiriON — XAItltATIVK. 45 



clings with the claw-like tips of its feet. The track must 1)0 made I)}- the catei-- 



pillai'S who come out of the case to feed and are said to \v;ilk aliout iu loiitr proces- 

 sions. Finally, after stripping; the trees of their leaves (in August when we 

 returned scarcely a leaf was to be seen on the trees on wliicli the empty, broken 

 ca.ses wei-e swinging about before the wind) they all come out of the case and 

 l)urrow into the ground and there cbrysaJate. Unfortunately we liad no means of 

 determining the insect to which the caterpillar belongs.* Travelling over the same 

 ground six months later, the trees were all once more green, and there was not a 

 trace of the cases to be seen. 



Many caterpillars li\'e in colonies, and some spin a web inclosing leaves and 

 twigs and so forming a nest or case for tliemselve.s, but in this instance the leaves 

 are not utilised, and the big bag hangs in the most prominent position, attached 

 usually to the smaller twigs at the ends of the gum tree branches. Nothing will 

 intei'fere with them owing to the exceedingly irritating nature of the excreta 

 which they contaiu, and the blacks believe that if this falls on your face you are 

 sure to be blinded. Serious results are known to have ft)llowed the tumbling 

 down of a case on to a white man sleeping under the gum tree from which it fell. 



The web is strong but nothing lil^e so tough as that of the two or three kinds 

 of " case-moths " found in the scrub. In each of tiiese, whicli is a small often 

 tubular bag one or two inches in length, there lives only a single caterpillar. 

 The latter carries its case about with it while it feeds, and tinally turns into the 

 chrysalis inside it, the male moth comes out at the lower end but the female is said 

 never to leave it, f never in fact developing any but the most rudimentary wings 

 and appendages. There are tinis several distinct kinds of protective cases or 

 houses made by caterpillars, some of which are concerned with single catei'pillars, 

 and otliers with social ones. The simjilcst is the irregubir webbing whicli serves to 

 fold over the edge of a leaf, and which is made by, and inclo.ses only, a single larva. 

 There are gradations in structure lietween tliis, and the most highly developed 

 form of house made by a single animal such as the common case-moth {^Metitra 

 clongata). 



Of cases inhabited l)y more than one lai'va the simpler are again made by 

 enclosing witii web, more or less regularly, leaves and twigs, whilst the most highly 

 developed is perhaps this large l)ag-case found in Central Australia, which may 

 serve as the hiding place for more than a hundi'ecl caterpillars. These cases or 

 houses must not be confused with tlie true cocoons that is the structui'es made liy 



* It is prolintilv .a species of the yemis Teaia. f There is some doubt about this. 



