56 



Mr. W. J. Lucas on the Emergence of 



of the accompanying figures, which are magaified about 

 23 times. It will be at once seen how admirably the 

 formidable larval mandibles are formed to serve as a 

 trap to catch the prey in that stage. The pupal jaws are 

 used in the insect's life for a single operation — the cutting 

 of an opening in the cocoon. They are much reduced in 

 size, and the slender hairs are perhaps vestigial only. 



3Iyr>neleon formicarius. 



\ 



3. Maudibles of Imago 



1. Mandibles of Lai-va 



■2. Mandibles of Pupa \ X abt. 23. 



The sharp points are well adapted for piercing the cocoon 

 and the saw-like edges are equally well suited for enlarging 

 the opening. In the imago the mandibles have become 

 quite simple in form and the hairs have disappeared. Of 

 two species of Cliryso'pa (C. septeniimnctata and C. dathrata) 

 whose pupal skins I possess, the jaws in that stage are 

 similar to those of the pupa of M. formicarius, and 



