452 Mr. David Sharp on the British Species of Agathidium. 
finely punctured, the latter with its sides narrowed anteriorly, 
though but little rounded; elytra closely and evidently punc- 
tured, with the humeral angles nearly right angles. 
Allied to 4. nigrinum, but smaller and narrower, with the elytra 
more acuminate behind and the punctuation of the upper surface 
more distinct throughout, but more sparing on the head. Judging 
from Thomson’s description of 4. arcticum, it must also be 
closely allied to that species, but in 4. arcticum the foveze between 
the eyes appear to be wanting and the tarsi in the male are not 
dilated, nor does there appear to be any form of that sex with 
an armed mandible. 
In A. rhinoceros the development of the left mandible of the 
@ is more remarkable than in any other species of the genus with 
which I am acquainted, but it varies extremely and is generally 
entirely wanting, having the mandible simple, as in the other sex. 
Sometimes there is a long blunt horn curved backwards and 
springing from the mandible a little before its apex, while some- 
times the mandible itself is prolonged and bent upwards into a 
horn; there are several distinct varieties of the first-mentioned of 
these forms, and the second gradually shades off to the unarmed 
variety. 
This species was found by Mr. Bishop and myself in consider- 
able numbers under the bark of a small fir stump at Rannoch in - 
the beginning of August, 1864. 1 know of no other examples. 
With this species I conclude the list of the British Agathidia, so 
far as our collections at present go. There are, however, several 
other species, some of which at least are likely to occur in this 
country. Among these may be mentioned A. badium, Ziegl., in- 
termediate between A. levigatum and A. seminulum, pitchy in 
colour, with the elytra slightly punctured and with no sutural 
stria; A. confusum, Bris., like rotundatum, but with the punctua- 
tion of the elytra more marked and with the anterior tarsi in the 
¢ only four-jointed ; 4. mandibulare, also like rotundatum, but 
impunctate ; A. arcticum, Thomson, is also not unlikely to occur 
in some of the northern parts of Scotland when those districts 
shall be properly searched. 
