A. W. Rymer Roberts 209 



short setae are situated and above them eight or nine pores of varying 

 size. 



The suhmentum, which constitutes the basal piece of the labium, is 

 strongly chitinised, elongate with parallel sides and the base bluntly 

 pointed. It extends from a point level with the bases of the maxillary 

 stipites to the point of insertion of the lacinia. Its anterior margin is 

 almost straight and it bears four long tapered setae in pairs at its anterior 

 and posterior angles. Many small pores are found on the surface. 



The mentum is membranous, nearly colourless, transverse and joined 

 at its sides for about half the length to the inner margins of the laciniae. 

 The anterior half is free. It is joined to the submentum just posterior 

 to the level of the insertion of the laciniae and is produced forwards 

 nearly to the level of the insertion of the galeae. The mentum is broader 

 than the base of the terminal lobe of the labium which succeeds it but the 

 angles are rounded off. 



The terminal lobe itself, composed of the fused palpigers and ligula, 

 is nearly pentagonal in shape. The labial palps are situated one on either 

 side of the anterior margin, while between them the margin protrudes 

 forwards a httle in a pale rounded projection, which is evidently the 

 ligula. Further back the palpigers may generally be roughly traced by 

 the darker colour of the cuticle on either side, that overlying the ligula 

 being pale and extending almost to the base of the apical lobe. 



A pair of setae are situated dorsally near the apex of the hgula, pro- 

 jecting forwards and a second pair occur ventraUy a little posterior to 

 the first. The longest pair are placed one on each palpiger at some dis- 

 tance from the base of the palp, while a fourth pair of quite short spines 

 are found not far from the base of each palpiger. 



In addition to the setae there are a number of pores on the ventral 

 surface of palpigers and ligula, as foUows: a row of three between the 

 two long setae of the palpigers, a single unpaired one on the left side 

 just behind them, and a pair behind the setae, followed by a single un- 

 paired median pore, while yet another pair occur almost in a line with 

 the short basal spines, one on the outer side of each. All these pores 

 appear to have a rather wide rounded margin with only a very minute 

 aperture (or perhaps a sensory pin) in the middle. 



The labial palps are each composed of two segments. The basal seg- 

 ment is stout and considerably rounded at the sides, especially on the inner 

 side. It is yellowish like the general surface of the cuticle, but is paler 

 at the apex. The apical segment is only about half the breadth of the 

 basal segment, brownish yellow, sUghtly turned inwards and gradually 



