DYTISCUS MARGINALIS. THE GREAT WATER BEETLE. 157 
at the bottom of the vessel. It will eat almost any insect, and de- 
vours raw meat with avidity. ‘Two seasons ago I had a large 
quantity of newts (the smaller newt and the Triton) in an aquarium. 
The female newts having deposited their eggs in the curled-up 
leaves of the water plants. Eventually I had some young newts 
which were extremely interesting to watch, especially the dranchia, 
or external gills, but they got less and less, until I had only one 
remaining, a much treasured prize. ‘The chain of destruction had 
been going on for some time, proving that a pond must be a lively 
place from time to time, newts versus worms, newts versus fish, 
then newt versus newt. As Iwas watching the little newt one 
afternoon, a patriarch of the newt tribe gobbled him up in a 
twinkling. This was too provoking. One aquarium contained 
only two tyrant newts, and the other a pair of Dytiscus beetles; 
as they had destroyed everything else, and had acted the tyrant 
too, I converted one of the tanks into a sort of Inch of Perth, and 
let them, like Hal of the Wynd, fight each for his own hand. 
During the first day, the contending parties kept aloof from each 
other. If the beetles were at the surface, the newts generally 
were at the bottom, and vice versa ; but the truce did not last long, 
for one of the beetles by swimming strongly to the surface at an 
angle of 45° caught one of the newts by the throat, got it immedi- 
ately on its back where it seemed quite powerless. In less than a 
minute the beetle released his hold, and the newt sank to the 
bottom quite dead ; the beetle having in that short space of time 
drained it of its life-blood. ‘The wound inflicted on the throat, as 
shown by a post-mortem made on the spot, was circular, and about 
the size of a No. 4 pellet. The beetle having proved himself 
easily victorious and being rather tiresome to keep, I put the pair 
into a phial and added a few drops of chloroform, having quite 
satisfied myself by the experiments alluded to, that a well-stocked 
pond must be to the inhabitants at least rather too lively to be 
pleasant, and after all the suitable insects are devoured. Unless 
the inhabitants can get out and betake themselves to pastures new 
like our friend the Dytiscus, they must do as the New Zealanders 
did before them. _ They are said to have eaten every specimen of 
the Dinornis, and then they set to work and ate up each other—so 
undoubtedly do the occupants of our ponds. Now that I have 
given you ample proof that Mr. Dytiscus is, for his size, a terrible 
tyrant, it will be refreshing to hear that even he has to succumb to 
one who is his master thoroughly: this is none other than “his 
missus.” She no doubt exercises her gentle sway and draws him 
with cords of love; but if he is not amenable to this treatment and 
it does not answer, she settles the difficulty by giving him what in 
sporting parlance might justly be termed an “awful milling,” not 
unfrequently leaving him dead on the battle field. A friend who 
