Longicornia of Australia and Tasmania. 169 
In a synopsis of the species of this genus (Ann. & Mag. 
Nat. Hist., ser. 6, vol. vil., Jan., 1891), I characterised 
P. nubilus from a male specimen taken at Port Essing- 
ton in North Australia. My determination of the species 
was, however, made from Pascoe’s description, and may 
possibly have been erroneous ; though, up to the present, 
I have not seen another species to which his description 
will better apply. 
Mr. Blackburn seems to me to have had a different 
species in view when he referred to P. nubilus, Pase., in 
the Transactions Royal Soc. South Australia, vol. xiii, 
pt. 2 (Dec., 1890), p. 130; and it is probable also that 
the species to which he refers as the Pachydissus austra- 
lasie of Hope is that which I characterised under the 
name of P. nubilis, Pasc. Hope’s description is so short 
and indefinite that it applies equally well to three or four 
different species, and for this reason I omitted it al- 
together from my synopsis. One character, however, 
mentioned by Hope, viz., “the third and fourth joints of 
the antenne subglobose,” seems to point to a species 
with rather short antenne. 
There is a species—represented in the British Museum 
collection by a male specimen from Port Kssington— 
which is very likely to be the Pachydissus australasie ot 
Hope, and which is only distinguishable from P. sericus, 
Newm., by the characters of the head. The eyes are 
larger and more approximated both above and below. 
The under side of the head has a single transverse groove 
in front, and a rather wide and shallow depression on 
the space between this and the post-ocular groove. 
6. Pachydissus, sp. 
Roebuck Bay. One female example. 
Closely resembles the females of P. sericus, Newm. ; 
but the under side of the head exhibits a different sculp- 
turing, and the pronotum is without a distinct subcentral 
smooth space. I am unable to refer it with certainty to 
any of the described species. 
The description of Pachydissus boops, Blackburn, so 
nearly fits the species named by me Pachydissus brevi- 
cornis, that the latter name must be considered a syno- 
nym. The synonymy will read as follows :— 
TRANS. ENT. SOC. LOND. 1893,—PaRT II. (JUNE.) N 
