106 Notes on Australian Coleoptera. 
false character, but for all that, as the insect on which it is 
formed, must be separated from Helluo, I propose to preserve 
the name in modifying its generic characters. 
Since Mr. Macleay has described, under the name of 
Helluo Grandis, an insect that appears to be the same, pro- 
bably another sex, but this fact is uncertain; it differs from 
Titana by the anterior margin of its thorax, which is ad- 
vanced and circular, and by the terminal article of its maxil- 
liary palpi being a little more securiform. Germar has also 
described a sort under the name of Helluo Longipennis, 
very nearly allied to the former. The sorts known to me 
as belonging to this genus are the following :— 
1. Gigadema Titana, Thomson, “ Arcan, Nat.” page 93, 
pl. 5, figs. 7, 8. : 
From Port Denison, Clarence River, and the region of the 
Lachlan River. 
2? Gigadema Grandis, Macleay, junr., “ Transactions of 
the Ent. Soc. of Sydney,” No. 2, p. 108. | 
From Port Denison. 
3. Gigadema Longipennis, Germar; “ Linn. Ent.,” vol. 3, 
, 162. 
; Generally from South Australia, but I have some specimens 
rather smaller from the Paroo River, and one other of the 
same size from Swan River. In many specimens the anterior 
thighs are considerably inflated. The tooth of the mentum is 
bilobated. | | 
4. Gigadema Bostock: length 17°; very nearly allied to 
the two preceding, but broader ; entirely of a glossy black; — 
head large, deeply punctured; thorax broad, cordiform, with 
the anterior angles protruding and rounded as in Longi- 
pennis; the disk shiny and without punctures, the margin 
densely coverd with them; a deep longitudinal sulcate in 
the middle; elytra strongly striated, with the intervals of 
the strie deeply punctured; legs and inferior parts of the 
body covered with strong puncturations. 
I received this insect from the Rey. Mr. Bostock ; it in- 
habits the northern parts of Western Australia. 
5. Gigadema Paroensis: length 11’; of a shiny black; 
covered with very strong puncturations which extend over 
the entire thorax with the exception of some small spaces 
on the disk; the thorax is cordiform, broad and straightly 
truncated in front; elytra moderately elongate, striated and 
strongly punctured; antenne hirsute, except on- the four 
basal articles. 
