BY R. J. TILLYARD. 



793 



the somewliat broad, flattened shape shown in Plate Ixxix., fig.4. 

 A slight pattern becomes noticeable upon the abdomen and 

 thorax, more markedly in some individuals than in others. This 

 is mainly due to the onset of pruinescence, which leaves the 



Text-fig. 3. 

 Cast skin of head of larva of Ps. elegans (Guer.), at second eedysis; ( x 30). 



original dull brownish colour of the body more definitely marked 

 mid-dorsally and in the sutures. A pair of darkish spots can be 

 made out on the meso- and metathorax, marking the positions of 

 the pinacula of these segments (see p. 800). 



At the end of the second instar, the larva has increased to 



