188 THE ENTOMOLOGIST. 
A NEW GENUS OF COLEOPTERA OF THE FAMILY 
PSEPHENIDA. 
By C. J. Gawan, M.A. 
re A 
Tur interesting and remarkable beetles which form the 
subject of the present paper were discovered by Dr. A. D. 
Imms, who found them in all their stages in rocky, swiftly 
running streams—the larve and pupe adhering to stones, and 
the imagines, newly emerged from their pupa-cases, resting 
submerged under stones alongside their empty pupa-cases. As 
Dr. Imms proposes to describe fully and give figures of the 
larvee and pupa, the imagines alone will be dealt with here ; but 
in referring them to the family Psephenide I have taken into 
account the habits of the insects and the great general re- 
semblance which the larve bear to those of Psephenus. 
One or two characters possessed by these beetles suffice to 
distinguish them from all other known Psephenide, and from all 
but a few genera of Coleoptera. (1) The elytra do not meet in 
the middle line to form a suture in any part of their length. 
When first I noticed this character I thought it might possibly 
be due to immaturity, as most of the specimens under observa- 
tion had apparently only just emerged from the pupa. But Dr. 
Imms was able to tell me that two specimens swept from grass 
and fully mature were like the rest in having the elytra rather 
widely separated from one another. (2) The middle area of the 
metanotum, behind the broad scutellum, is not grooved along 
the middle (as it is in the great majority of beetles), but is 
convex along the middle and marked with a groove along each 
side. This character is evidently correlated with the first, and 
shows pretty conclusively that the elytra never do meet in the 
middle line. We find the metanotum similarly devoid of a 
median groove in the heteromerous genus Rhipiphorus, in which 
the elytra are small scale-like structures, which do not meet 
