NO. TO 



MORPHOLOGY OF GNATriOTRICHUS SCTIEDL 



21 



Gtila. — The gula is bounded by the two very closely placed gular- 

 sutures (figs. 6, 7. Gus) and widens anteriorly to form the pregula. 



Ge Ge 



Pr- 



Oct-'-- 



Cos 



--Oca 



Fig. 6. — Gnathotrichus sulcatiis Lee. : Head, ventral aspect. 



An, antenna; Cos, coronal suture; £v, compound eye; Ge, gena; Gus, gular sutures; Hy, 

 hypostoma; La, labium; Md, mandible; Mx, maxilla; Oc, occipital area; Oca, occipital 

 apodeme; Oct, occipital foramen; Pr, pregula; a, dorsal articulation of the mandible; b, 

 ventral articulation of the mandible; c, antennal groove. 



B 



Fig. 7. — A, Gnathotrichus snlcatus Lee. : Head, oral aspeet. B, Gnathotrichus 

 retustis Lee. : Pregula. 



An, antenna; Ef>, epistoma; Gc, gena; Gus, gular sutures; Fr, frons; Hy, hypostoma; 

 La, labium; Mx, maxilla; Pr, pregula; SE, serratus epistomalus; a, dorsal articulation of 

 mandibles; b, I'entral articulation of mandibles; c, antennal groove. 



These two distinct sutures appear to be exceptional in this family. 

 Hopkins apparently did not find any double sutures in his investi- 

 gations. 



