76 Psyche [April 



tips, and form the labium. The antennae hang down with the 

 legs. All the trophi are larger and more developed. The eyes 

 are not yet visible. 



10th day. (Fig. 6) The head is well formed with the eyes 

 partly pigmented. The antennae are long and repose in a ventral 

 position between the first pair of legs, their basal part and the 

 head-capsule having begun to grow forward to cover the bases 

 of the mandibles and maxillae. The labrum and clypeus are 

 much longer and free. The mandibles are fiattish bodies about 

 twice as long as broad, lying above the maxillae. The maxillary 

 setae have become twice the length of the mandibles and fiattish, 

 the maxillary plates have altered but little, and still retain a 

 slight connection with the setae at their bases. The 2nd maxillae 

 have coalesced to near their tips and are more distinct. 



11th day. (Fig. 7) The head is distinct and the eyes much 

 more pigmented. The bases of the antennae have grown more 

 forward along with the head-capsule, and enveloped the base 

 of the clypeal region. The labrum is elongated. The labium 

 is one piece with three distinct joints, and a more obscure basal one. 



12th day. The articulations of the mandibles to the head- 

 capsule have begun to assume their ginglymus character. 



13th day. (Fig. 8) The forward movement of the head- 

 capsule and base of antennae has continued considerably, the 

 bases of the mandibles and maxillae appearing to be within the 

 head-capsule. The lateral edges of the labium have begun to turn 

 up and form the groove in which the setae eventually repose. 



IJ^th day. (Fig. 9) The false sutures in the head-capsule 

 are plain, showing the forward movement of the head-capsule 

 and its fusion with the clypeal region, leaving only the labrum and 

 the epipharynx free. The setae are more slender and rod-like. 

 The labium is distinctly grooved. 



15th day. The head is more chitinized and pigmented, the 

 greatest change being the more definite shape of the maxillary 

 plate, the dorsal edges being in contact with the lateral edges 

 of the labrum, and its ventral edges partly fixed to the basal 

 part of the labium. The ginglymus articulations of the mandibles 

 are distinct. The only connection between the maxillary plate 

 and seta is by the protractor muscle. 



16th day. (Fig. 10) The forward part of the head-capsule 



