I. TRÄGÅRDH, METAMORPHOSIS AND BIOLOGY OF ORCHESTES. 5 



flat., ovoid and placed so far backwards, that they do not 

 project beyond the anterior margin. 



The shape of the body is better described in connection 

 with the changes which the larva undergoes during its 

 growth. 



2. Changes during the growth of the larva. 



During the 1st stage (Fig. 5, Pl. I) the larva has no 

 markings on the body, and the cuticle is quite smooth. The 

 colour is yellowish-white. The shape is also different from 

 that of the låter stages, in so far that the body is widest 

 in the prothorax, tapers less and more slowly backwards and 

 is of even width for ^3 of its length. 



The intersegmental constrictions are small and there are 

 no lateral projections. 



The length is l,i mm., the width 0,3 6 mm. The most 

 interesting feature is, however, that the tergite of the proto- 

 rax is not developed as a plate, as in the låter stages, and 

 the head is not covered by its anterior edge, but quite free. 



These changes take place in the 2nd stage. 



The second larval stage (Fig. 6, Pl. I) has not in- 

 creased much in length, compared with the Ist one, (comp. 

 figs. 5 and 6 Pl. I) but the head is considerably larger and 

 the thoracic segments ha ve become much wider; furthermore 

 the prothorax is protected by two rectangular shields, rounded 

 at the sides and separated one from another by a narrow 

 median streak of soft cuticle. The prothorax has increased 

 very considerably in size, and is now as long as themeso-and 

 metathorax together and slightly wider; its anterior edge 

 projects round the base of the head capsule, which it em- 

 braces, so that on dorsal view the portion behind the posterior 

 tip of the fröns is completely hidden. 



On the ventral side the edge of the prothorax projects 

 still more and the surface is protected by a large smooth 

 shield. 



During its further growth the larva does not undergo 

 such marked changes as those which have been described above. 



The lateral projections of the segments, which in the 

 2nd stage were very low and rounded, increase in size, be- 



