12 Mr. F. Muir and Dr. D. Sharp on 



At each ecdysis the old skin is retained on the ninth 

 abdominal spike and also the filaments attached to it. 



The long black filaments shown in figures 23a, h, c, d, 

 are the excrement of the creature. They are, of course, 

 not pi'escnt when the larva is first hatched out ; but 

 all the filaments that are subsequently produced are 

 retained till the imago emerges ; the crop of them pro- 

 duced during each stadium remaining attached to the old 

 larval skin. We do not know how these filamentous ex- 

 crements are produced, and there appears to be no authentic 

 information on the subject in literature. 



The pupa varies from yellow to green in colour. The 

 spikes round the pronotum and abdomen are slightly 

 bordered with black, and a dark mark runs down each 

 side of the back. The pronotum is expanded into a semi- 

 transparent shield surrounded with fine spikelets, two pairs 

 of which are ofttimes larger than the rest. The pro- and 

 metanotum lose all traces of spikes. 



The first five abdominal spikes become flattened into 

 thin transparent lancoelate membranes surrounded with 

 small spikes. The remaining four pair of spikes are 

 greatly reduced in size, and the ninth pair hold the cast 

 larval skins and attached, intestinally-made filaments. 



The use of excrementitious filaments reaches its maxi- 

 mum * in ^. tigrina, and the larva with its array of 

 bristles and its complex series of excrementitious ap- 

 pendages is a truly wonderful object. 



5. Basipta stolida. 



PI. V, figs. 2irt— 24(/. 



The adult larva of this species is whitish, the thorax 

 being marked with brown and a dark mark runs down 

 each side of the back. When first hatched out it is 

 nearly all black. 



The spikes surrounding the larva are numerically the 

 same as in A. pundicosta but are proportionally smaller 

 and not so beset with bristles. The ninth abdominal 

 spikes are greatly enlarged, thick, strong and curved at 

 the tips ; they are a dark colour below and light above, so 



* That is to say, so far as the species we are here dealing with are 

 concerned. The Brazilian Porphyrasjns tristis far surpasses A. 

 tigrina, but uses the wonderful filaments it produces in a totally 

 different manner. 



