I. TRAGARDH, METAMORPHOSIS AND BIOLOG Y OF ORCHESTES. 3 



The cuticle (Fig. 4, Pl. I) has numerous, more or less 

 semisphasrical thickenings or granules, which are arranged in 

 transverse rows; on the lateral projections of the body they 

 are slightly pointed and directed backwards. 



On the places, where the blackish spöts are situated, 

 the granules are dark-coloured, placed more closely and 

 coalesce as to form narrow bands. 



The head (Fig. 6, Pl. II) is of a dark brown colour; 

 its base is partly concealed within the prothorax, which en- 

 closes it in a fold of soft cuticle. The head capsule is flat- 

 tened dorsoventrally and curved shghtly downwards; the 

 part which is visible on dorsal view is semicircular in out- 

 line and shghtly obtuse in the middle. 



The head capsule is remarkable through the great deve- 

 lopment of the fröns, which occupies nearjy V3 of the upper 

 surface and projects backwards nearly to the hind margin; 

 the fröns has a dark median interiör ridge, and is separated 

 from the two halves into w^hicli it divides the vert ex b^^ a 

 pair of narrow streaks of transparent cuticle which form a Y. 

 The fröns is triangulär and as broad as it is long, its anterior 

 margin is thickened like a ridge. 



The vertex sclerites project backwards, so that the hind 

 margin of the capsule becomes convex. 



The clypeus (Fig. 11, Pl. II) is short, but very broad; 

 the anterior margin is excavated and by a narrow band of 

 soft cuticle separated from the labrum; posteriorly it is thick, 

 strongly chitinous and firmly coalesced with the anterior 

 edge of the fröns; at the sides we notice a pair of rounded 

 projections, which form the upper condyli for the mandibles; 

 is has three pairs of small, slender hairs. 



The labrum (Fig. 11, Pl. II) is elongated hexagonal and 

 nearly twice as broad as it is long. On the upper side we 

 notice two pairs of slender, pointed hairs, arranged in a 

 transverse row, parallel to the hind margin. 



The anterior edge and the ventral side is provided with 

 some very remarkable bristles; on the ventral side (Fig. 15, 

 Pl. II) in the middle, we notice two narrow, posteriorly con- 

 verging ridges, on which are inserted 3 pairs of large, hook- 

 shaped bristles, curved towards the median line; at the 

 anterior edge there are 5 pairs of bristles, the two lateral 

 pairs of which are stouter than the others, more sharply 



