FENTOMOSTRACA NEW TO THE FAUNA OF ORKNEY. _-~ 93 
slabs on end. We think of the numberless genera- 
tions that have existed and passed away since 
that far-off time, while like lone sentinels .these 
monuments have stood through sunshine and storm 
telling of the insignificance of human life, and the old 
question imperceptibly forces itself upon the mind— 
“What is man that Thou art mindful of him, or 
the son of man that Thou shouldest visit him?” - 
As we turn away, a gleam of encouragement 
strikes athwart these gloomy reveries with the 
thought that the good as well as the “evil that men 
‘do lives after them,” even though their personality 
be lost in oblivion. 
Whether this and similar circles were formed for 
religious purposes, or for commemorating some great 
battle, or in honour of some great hero, is only 
matter of conjecture and seems likely to remain 
so; but the stones themselves will continue to 
be viewed by the ignorant with superstitious 
awe, while, to the intelligent and devout mind, 
thoughts full of interest and instruction will be 
suggested. Numerous other stones, mostly solitary, 
are scattered over this part of the mainland, all 
of which appear to be of equally ancient date; and 
possibly many of these single stones may be monu- 
mental in their significance. 
At the south end of the “Bridge of Brogar,” and 
on both sides of it, were some shallow weedy pools, 
and a ditch by the side of the road leading down to 
it that had the appearance of being suitable habitats 
for Entomostraca. These were the only places I had 
time to try my tow-net in. On examining the 
material collected in these places, I found that 
besides other things there were at least ten species 
of. Ostracoda, which are as follows: 
Cypria ophthalmica (J urine) (= Cypris compressa, - 
Baird). 
es levis (C. F. Miiller) (= Cypris ovum, J urine). 
= serena (Koch) (= Cypris levis, Brady). 
Cypris prasina, Fischer (= Cypris salina, Brady). 
