277 



perhaps by my tabulation of the Australian Sericoid genera 

 be referred to Burrhomorpha, on account of its clypeus being 

 lightly emarginate across the front. (S'. 'paUUlnla is, as indi- 

 cated above, an isolated form which may prove, when its sexes 

 are known, to require the formation of a new genus (as Mac- 

 leay forecasted). It is, however, very far removed from 

 ByrrJiomorpha which is a genus of extremely robust coarsely 

 sculptured insects with hind tibiae very stout and strongly 

 dilated at their apex; while S. qmUidida is altogether of the 

 Scifrda build, — of fragile form and having hind tibiae elongate 

 slender and almost without apical dilatation. 



OCNODUS. 



The pres-ence of conspicuous tufts of hairs on the under 

 surface of the tarsal joints seems to be the most noticeable 

 character of this genus. The extremely short hind coxae also 

 furnish a noteworthy character. The antennal structure, 

 judged by the species as yet known, seems to be uniform — 

 which is very unusual in the Australian Sericoidcs. The 

 structure of the labrum is extremely variable and furnishes 

 a valuable specific character. The form of the hind angles 

 of the prothorax is most remarkable. In all the species 

 known to me these angles are really obtuse or subrectangular, 

 but owing to the curve of the convexity on the dorsal surface 

 (except perhaps in 0. Inguhris, Blackb.), they appear acute or 

 even spiniform if the prothorax be looked down upon from 

 directly above it. I have now three additional species before 

 me which are described below. The following table shows 

 characters by which the species known may be distinguished. 



It is possible that some of the insufficiently-described 

 species of the earW authors (discussed by me under the head- 

 ing of Srifala, &c.) may be attributable to this genus, but I 

 think it improbable, as the genus is not known to occur in the 

 localities where most of the species in question were found. 



When I described the Coleoytera of the Elder Expedition 

 I attributed to this genus with a strong expression of doubt a 

 species which I described under the name ferrugineus. I am 

 now satisfied that it must not remain associated with the other 

 species referred by me to Ocnodus, and that its real affinities 

 are with Cciidobius, under which generic name I have already 

 recorded it (above) in this memoir. 



I must here repeat what I have already notified, viz., thac 

 since I have never succeeded in identifying the typical species 

 of Oc7iodus (0. decipiens, Burm.) there is a doubt whether 

 the species to which I have applied the name Ocnodus are 

 really congeneric with Burmeister's insect. It will be well 

 to remember that the generic position of those species will be 

 best expressed by calling them Ocnodus, Blackb. ( ?Burm.). 



