194 



by them. The larger ones are usually crowned with scales 

 that are darker than the surrounding ones. The type is 

 probably a female. 



DiETHUSA ACUTicoSTA, Lea. 

 The female of this species has the four front tibiae as in 

 the female of hlachhurni. A specimen from Port Lincoln 

 exhibits the curious apical dentition quite conspicuously. On 

 the type female the tibiae w^ere clogged with gum, and so the 

 dentition was overlooked. 



DiETHUSA BLACKBUENI, Lea. 



The type of this species is clothed with almost uniformly 

 white scales, the feebly-spotted appearance of the elytra being 

 due to somewhat irregular disposition of the scales rather than 

 to shades of colour. It is a female ; the male differs in having 

 each of the four front tibiae with the apical tooth in the 

 normal position. The rostrum is shorter, with larger and 

 denser punctures, condensed into strong but partially- 

 concealed rows behind antennae, and the antennae are inserted 

 somewhat nearer its apex. The basal segment of its abdomen 

 is slightly concave (instead of distinctly convex) and has a 

 curious line of stramineous clothing along its middle and con- 

 tinued on to metasternum. 



DiETHUSA FAMELICA, Lea. 



The types of this species were described as having the 

 abdomen with '"the three median segments so depressed that 

 their lengths can only be seen from the sides" ; this, however, 

 was due to the apex of the abdomen, in each, being somewhat 

 protruded. On specimens with the abdomen in its normal 

 position the length of the second segment is easily seen, but 

 the third and fourth are depressed below its level and the 

 level of the fifth ; and as they are extremely short if the 

 tip of the abdomen is at all free from the elytra (as it fre- 

 quently is) they are almost concealed. 



The clothing is dense and variable. A specimen from 

 Blackburn's collection has the scales on the upper-surface 

 dark-bro^vn, but with an appearance as of numerous short 

 whitish stripes (along the striae) on the elytra, and the pro- 

 thorax with a median line and white patches on the sides. 

 Other specimens (from Murray Bridge) have most of the scales 

 pale, but with numerous sooty or dark-brown spots (not 

 symmetrically disposed) on the prothorax and elytra. No 

 two, of the fourteen specimens (including one from Birchip 

 in Victoria) before me, agree in their markings. 



