HORN EXPEDITION—COLEOPTERA. 
261 
eyes more prominent. The genei’al form, moreover, is much like that of exsculplus. 
The elytral sculpture resembles that of the European O. pypmoius^ Fab., but the 
strife are scarcely so strongly-impressed, and the interstices are wider and more 
conspicuously flattened. 
lleedy Hole. 
HYDR.ENA. 
H. sitnplicicol/is, sp. nov. (9). Oblonga ; postice vix dilatata ; supra obscure 
brunnea, capite picescenti j clypeo subtilissinie, capite postice magis fortiter- 
prothorace confertim sat subtiliter punctulatis ; hoc fere fequali, lateribus modice 
arcuatis; elytris subtiliter punctulato-striatis (striis nec puncturis postice 
obsoletis), ad apicem obtusis; subtus piceo-nigra, antennis palpis pedibusque 
lividis. Long, i 1. Lat. 1. 
Differs from the previously-described Australian Hydrcence^ except luridipennis, 
Mach, by the blunt apex of its elytra. H. luridipennis is insufficiently described, 
but one character is mentioned that seems to distinguish it from the present insect, 
viz., “ sides of prothorax bulged out almost angularly in the middle.” I have a 
Hydrcena from Queensland which appears to me to be H. luridipennis, and it differs 
from H. siniplicicollis also in the much less line puncturation of its prothorax. 
Paisley Bluff*, lleedy Creek, Ellery Creek. 
H. rudullensis, sp. nov. (1). Oblongo-ovalis ; nitida ; supra obscure brunnea, 
capite picescenti; supra subtilis,sime vix manifesto punctulata, puncturis in elytris 
subseriatim dispositis ; his postice obtusis. Long, 1. Lat., ^ 1. 
This minute species diti’ers from all the other described Australian species of 
the genus by its non-striate elytra and excessively line puncturation. 
lludall’s Creek. 
CYCLONOTUxM. 
C. Mastersi, Mach (6), Palm Creek, Ellery Creek, Rudall’s Creek. 
N.B.—Besides the Hydrophilidte enumerated above, the collection contains an 
exceedingly minute insect (from lleedy Creek) scarcely ^ 1. long, which appefirs to 
belong to the family, but is too much damaged for satisfactory determination. 
