192 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I37 



We have not found a trace of a salivary muscle either in cross or 

 longitudinal sections, nor on the preparations in toto. It therefore 

 seems that the swaying movements of the labiohypopharyngeal 

 complex contribute toward evacuating the product of the secretion 



-MPhdm 



Mann 



MSto-J^ 



DJLab 



1..r.ti 



7/10 mm- 



MSLi 



Mrao 



M\b Md 



-MadMd 



cm 7 tii/ ^L,..S^.._.. 



CS MPrm MLac 



Fig. 10. — Macropclopia cf. nebiilosa Mg. 



Parts of the two cross sections passing almost to the posterior quarter. The 

 upper figure shows the connections of the rao blending together the slender 

 antennal muscle between its two divergent fiber groups. The lower figure passes 

 farther forward and shows the level of insertion of rao on the suspensorium. 



of the prothoracic labial glands; it is true that the Tanypinae larvae 

 do not construct silken cases. 



The mobility of this whole structure is then rather great, much 

 greater than that of the homologous ofgan in the orthocladian larvae. 

 In effect, the retractors angulorum oris (Mrao) reverse the complex 

 in the stomodeal lumen, the premental and hypopharyngeal teeth by 



