58 
species closely related to Sisyriwm seems to be most difficult. M 
Lacordaire says that complete identity exists between that genus 
and Acyrusa, except in the latter having a spine at the apex of 
the third joint of the antenne, and a pubescent fovea on either 
side of the basal four ventral segments. I have not seen any 
species presenting these characters, but I have before me an 
insect from western 8. Australia, and another from near Ade- 
laide, having a pubescent fovea on either side of the third and 
fourth ventral segments, but no spine on the antenne. I have 
also a species from western 8. Australia having the antennal 
spine, but no ventral fovez ; and a fourth species from the same 
locality devoid of both characters, neither of which appears to be 
sexual. The last-mentioned of the above species is possibly, but 
not probably, a variety of S. stigmosum, Pasc.; in any case its 
differences from stegmosum are so strongly marked that a distinc- 
tive name seems desirable ; the others appear to be new. 
As it seems absurd to go on making a new genus for every new 
species among insects that might at a casual glance almost pass 
for being mere varieties of a single species, it seems to me desir- 
able to call them all Sisyriwm, as none of them possess both the 
characters on which Acyrusa has been distinguished. The last of 
the following species has the maxillary palpi much longer than 
the labial (a divergence which M. Lacordaire allows within the 
limits of the allied genus Callidiopsis), and also has the anterior 
coxe more prominent than is usual in the subfamily; a little 
more prominent even than in Diatomocephala. 
S. stigmosum, Pasc., var. ? vittatwm. 
A §. stigmoso differt colore. Rubro-ferrugineo, elytris nigro- 
notatis, macula antica in vittam nigro-piceam (a basi ad 
fasciam antiapicalem integram) elongata ; prothorace quam 
latiori circiter quarta parte longiori; pedibus unicoloribus. 
Long., 43 1.; lat. 1 1. 
Apart from the characters mentioned above, the description of 
S. (Igenia) stigmosum applies very well to the present insect. It 
will be noticed that the colouring and the pattern on the elytra 
are considerably different, and that the prothorax is very much 
less elongate than that of §. stegmoswm is said to be. Unless, 
however, Mr. Pascoe measured the proportions, his statements on 
the point are probably worthless, as the proportions of a pro- 
thorax are in few instances by measurement the same they 
appear to a casual glance. 
S. Australia ; near Port Lincoln. 
S. fraternum, sp. nov. Setis erectis sat sparsim vestitum ; 
ferrugineum, elytris macula communi (literam U simulanti) 
nigro-fusca ornatis ; capite fortiter minus crebre punctulato 
