80 MISS K. H ADDON ON THE 



The maxillae have on their ventral aspect a small square plate 

 (cd.) representing the cardo, and a larger more elongated stipes 

 (si.), which bears a few long bristles and some short flattened hairs. 

 Externally is a stout four-jointed palp (mx.p.) with a few hairs, 

 and internally a two-jointed palp-like galea (ga.) and a flat 

 lacinia (la.), both covered profusely with hairs, the inner margin 

 of the lacinia bearing a row of stiff bristles. Dorsally, the 

 maxillae have much the same appearance, except that the cardo is 

 not represented and the stipes is small. At the base of the palp 

 along the external border is a, tuft of hairs pointing forward, as 

 do all the hairs on these mouth-parts. Posterior to the tuft are 

 a few more of the short flattened hairs, which are similar to those 

 described by Packard * as taste-hairs. 



The ventral view of the labium shows the transversely placed 

 submentum (sm.) tapering from each end towards the middle. 

 The mentum (mi.) is in the shape of an elongated triangle, the 

 apex being anterior ; it bears a few bristles and some short 

 flattened hairs. Distally, there is a pair of short, fat, three- 

 jointed palps (la.]).), with a few hairs. 



Dorsally, there is a clump of hairs at the base of the palps, and 

 another larger one more posteriorly. 



Labrum. 



The shape of the upper lip (fig. 6) is roughly trapezoidal, the 

 anterior margin being the longest, and slightly indented in the 

 middle. Posteriorly there is a deep bay, formed of a fork of 

 chitin (c.f.) which protrudes beyond the rest of the labrum ; the 

 handle, as it were, of the fork forms the main support, or 

 mid-rib (mr.), of the labrum, and bears two wing-like lateral 

 expansions which keep the whole rigid. 



Dorsally the surface is slightly rounded, but on the underside 

 there is a mid- ventral ridge formed by the junction of the two 

 sides, which slope steeply down towards it. There is on each 

 antero-lateral corner a socket which receives the condyles on the 

 mandible. 



The whole of the ventral surface of the labrum is covered with 

 numerous rows of tiny hairs, all of which point forwards. The 

 rows themselves are arranged across the labrum, but slope forward 

 from the sides towards the mid -ventral ridge. The anterior 

 margin is beset with stiff bristles which bend slightly towards 

 the middle. 



The Hypopharynx. 



The tongue, or hypopharynx (fig. 7), is in the shape of a tri- 

 angle with the base bulged out ; the apex is directed forwards, 

 while at each end of the base is a chitinous knob (art.) articulating 

 with a strut from the side of the head. With the exception of 

 these knobs the hypopharynx is completely covered with hairs 

 pointing forwards, as usual. 



* A. S. Packard, 'Textbook of Entomology,' 1898, p. 282. 



