1 84 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. T37 



Pocc 



Fig. 6. — Lasiodiamcsa gracilis K. 



The ventral view, a little oblique, of the head shows (i) the netlike disposi- 

 tion of the labral and epipharyngeal elements designated according to Zavfel 

 (1941) ; (2) the two groups of the centroepipharyngeal chaetae (chli, chh; 

 (3) the little labral rod (;r) beside the torma, and which Zavfel considers as 

 the premandible ; (4) the tentorium. The mandible, of which the ventral brush 

 is disposed in a line, is concealed by the maxilla. The hypopharynx and the 

 labium are not figured; they are situated in the space between the mandibles, 

 the maxillae, and U-shaped piece, and the hypochilum. The even-numbered 

 organs and elements (except SI, SII, SIII) are figured only on one side. 



