104 Notes on Australian Coleoptera. 
Helluomde. 
This tribe, entirely absent in Europe, is numerously repre- 
sented in Australia; all its sorts were till lately placed 
under the generic name of Helluo, but the researches of 
modern entomologists have lmited that genus to the only 
species on which Bonelli had established it, Hel/us Costatus, 
first brought to Kurope by Peron, the learned naturalist of 
Captain Baudin’s expedition. To this insect, Baron 
Chaudoir adds (“Bulletin de Moscou’) a sorthecalls Carinatus, 
which is not well known to me. I received one specimen 
under that name from Count de Mniszech, but it is so very 
closely allied to Costatus as to be very difficult to distinguish 
from it. It is thought certain that some of the specimens 
found near Sydney differ considerably from those of Mel- 
bourne and Tasmania. 
Mr. Lacordaire states erroneously that in this family the 
tarsi are similar in the two sexes; in the Melbourne Helluo, 
which I believe to be the same as Costatus, the anterior 
tarsi of the male are dilated. 
The Helluonide of Australia can be divided in the follow- 
ing manner :— : 
A. Body without wings— 
a. Antennz not compressed, but more or less cylindrical. 
* Labrum covering almost or entirely the mandibule. 
s. ‘Tooth of the mentum short and obtuse (Helluo. ) 
ss. ‘Tooth of the mentum very long, slender and acute | 
(Pseudhelluo). 
** Labrum square, not covering the mandibule (Acro- 
gonys). 
aa. Antenne compressed (Helluodema). 
B. Body with wings— 
a. A tooth to the mentum. 
* Head oval ( Gigadema). 
** Head inflated behind the eyes (Helluosoma). 
aa. No tooth to the mentum (4inigma). 
Pseudhelluo has the general form of Anigma, but is 
easily characterised by its very large labrum covering 
entirely the mandibule and its mentum having in its centre 
a long spine; the wings of that organ are also very long ; 
the last article of the palpi is conical; the anterior tibie 
are sulcated and very strongly emarginated. 
