SOME TASMANIAN CASE-BEARING LEPIDOPTERA. 311 



diminutive wave-like manner, which turns it over on to its face 

 again. The body then regains its normal size. I have found, 

 after repeated experiments, that the wave-like motion will propel 

 the body forward 1 mm. on a smooth surface. 



This species is the most plentiful of any case-builder moth in 

 Tasmania. The larvae feed on various species of eucalyptus and 

 acacia, also sweet-brier, and occasionally other plants. I have 

 lately been studying the habits and development of this species, 

 and have been both surprised and delighted at what I saw. 



For some time entomologists could not agree as to whether 

 the members of the family Psychidse did really lay eggs, or 

 whether the young hatched from within the body of the parent. 

 Prof. McCoy, in Decade IV. of ' Prodromus of the Zoology of 

 Victoria,' says : — ". . . Immense numbers of young are brought 

 forth, not in the egg-state, as hitherto supposed for all moths, 

 but as exceedingly minute perfect larvte. In confirmation of 

 this unexpected discovery, I may mention that no eggs are ever 

 found in the cases of the species observed in this colony, and the 

 myriads of young produced by each female may be observed 

 emerging in a continuous stream as minute larvse, under circum- 

 stances which render it impossible to suppose that eggs could 

 have been deposited." 



Entomological science has advanced much since the above 

 quotation was penned, and we have learned that the females of 

 the Psychidge really do lay eggs ; but the manner of laying them, 

 and the behaviour of the females after the operation, is not so 

 well known to the bulk of entomologists. Before proceeding to 

 the actual egg-laying, let me say that the females of the par- 

 ticular species under discussion are enclosed in brown pupa- 

 cases tapering at the anterior end, but rounded at the other 

 extremity. They are fixed midway in the case. The segments 

 are distinctly marked. When the females are ready to copulate 

 the bottoms of the pupa-cases drop off. Copulation then takes 

 place ; the males have to insert at least two-thirds of their 

 abdomens into the outside cases in order to reach the females. 

 The abdomens of the males are capable of great extension. 

 After copulation the females icriggle out of their close-fitting prisons, 

 turn head doiunwards, and icriggle hack again, so that tlieir lieads 

 just project beyond the posterior extremity of the pupa-cases. Egg- 

 laying then commences, and continues until one-fourth to one- 

 third of the cases are filled. The eggs are bright yellow and 

 round ; with them is packed a little short yellow fluff from round 

 the ovipositor of the females. By the time egg-laying is finished, 

 the females are hut shadoivs of their former selves ; they then drop 

 out of the pupa-cases, and fall to the bottom of the '^cases'' or 

 " sacks," and there shrivel and die. In a few days they are mere 

 tiny scraps of brown dried skin. The number of eggs laid varies 

 from two hundred to five hundred. Several writers on the 



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