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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 82 



The lacinia bears on the anterior portion of the free dorsal margin 

 short, stout, bknit setae (f ) which are sHghtly incurved at their tips. 



Fig. 13, A. — Gnathotrichus retusus 

 Lee. : Labium, ventral aspect. 



L, ligula; M, mentum; Pp, palpifer; a. 

 liase of ligula; b, neck of mentum; c, ventral 

 setae of the palpifer; d, anterior part of 

 ligula; e, first joint of palpus; /, second joint 

 of palpus; g, third joint of palpus. 



Fig. 13, B. — Gnathotrichus retusus 

 Lee. : Labium, dorsal aspect. 



P, palpus; L, ligula; a, articulation of the 

 labium; b, base of ligula; c, dorso-lateral 

 setae of the palpifer; d, dorso-anterior setae 

 of the ligula; e, f, g, first, second, and third 

 joint of the palpus. 



Fig. 13, C. — Gnathotrichus sulcatus 

 Lee. : Labium, ventral aspect. 



Fig. 13, D. — Gnathotrichus sulcatus 

 Lee. : Labium, dorsal aspect. 



These setae gradually become longer, more slender, and pointed pos- 

 teriorly (e). Near the subgaleal area (fig. ri, d) they are about three 

 times as long as on the dorsal margin. Besides these setae on the outer 



