444 APPENDIX I 
It was first described from Lapland, and is very common in Lab- 
rador, but occurs nowhere else in America. It is a narrow, slender 
insect one-quarter of an inch long, yellowish brown, with the head 
and a band across the thorax (or middle portion of the body) 
black. The wing cases are quite rough and uneven. 
The other beetle which I 
sought in the beginning from 
my Labrador friends (A gabus 
infuscatus Aube) is appar- 
ently even more common 
there than the one in the 
illustration. It has been re- 
corded from Mount Wash- 
ington and Lake Superior, 
but it is certainly not com- 
mon at either of these points. 
It is shorter and more robust 
than Agabus arcticus; the 
wing covers are brown, the 
head and thorax black. 
The large water-beetle 
shown in the next figure (No. 
22 Dytiscus dauricus Gebl) 
is one of the largest of the 
Labrador beetles, being an 
inch and a quarter long. It 
is greenish black, with the 
borders of the thorax and of the wing covers yellow. The under side 
of the body is yellow, with several black lines and markings. The 
beetles of the genus Dytiscus are probably the most highly devel- 
oped of all beetles. The males have the three basal joints of the 
front tarsi (the last segment of the leg) enormously dilated and 
enlarged into a large circular disk, the under side of which is cov- 
ered with a large number of palettes, some large, some small. The 
middle legs are similarly modified, but to a less degree. These 
disks are of use in enabling the beetle to cling to objects, and are 
probably also very sensitive organs. The females do not have 
these disks at all, but, on the other hand, they often have deep 
grooves or furrows extending longitudinally halfway or more along 
the wing covers. 
While speaking of water-beetles, it is interesting to note that 
they all possess real wings and are capable of flying great distances. 
In countries where there are artificial lights, the beetles are often 
attracted to them and are sometimes found many miles away from 
any water. 
Dytiscus dauricus. 
