l!Y R. J. Tll.IA \l!l>. 



435 



The labrum (Text-fig. 6a) is closely similar to that of Psychopsis, 

 but there is a delicate lobe attached to it on the inner side, 

 which appears to represent the epipharynx. As the figures for 

 Psychopsis were not made from fresh specimens, it is possible 

 thai the epipharynx may have been shrivelled in these, and was 

 thus overlooked. 



The mandibles (Text-fig.66) are of the primitive Panorpoid 

 type, elongated, pointed, and without internal teeth. Those of 

 the male are longer and sharper than those of the female. They 

 differ from those of Psychopsis in not possessing any inner broad 

 lobe. The difference may be correlated with the absence of a 

 cocoon in the pupal stage of the Ithonidce; if so, then the form 

 of mandible found in the imagines of Psychopsidce is partially 



Text-fig. 6. 

 ft/tone fusca Newm. Mouth-parts of male, a, labrum and epipharynx; 

 b, left and right mandibles; C, left maxilla, with cd, cardo, ga, galea, 

 la, lacinia, mxp, maxillary palpus, and st, stipes; d, labium. (All 

 x 30). 



due to specialisation in the pupal stage, in which, as I have pre- 

 viously shown (10, p. SOS, Text-fig. 10) the mandibles are more 

 strongly formed than in the imago, and are used for cutting open 

 the cocoon. Of what use the mandibles are to the Ithonidce I 

 do not know, as these insects appear to live only a few days; 1 



