The Ancient Lakes of Edinburgh. 127 
for what they are in themselves, and the circumstances and 
conditions they represent—still waters and green pastures— 
but also for the contrast they afford to the fire-raised rocks 
or the ice-laid hillocks they lie among. The crags remind 
us of volcanic eruptions with lava streams and clouds of 
ashes, earthquakes and rock-rendings, or injections of molten 
matter; and the hillocks remind us of ice in all its varied 
forms and actions—ice-sheets, glaciers, and icebergs,—disrupt- 
ing rocks by ice wedges, and grinding them to powder by its 
pressures exerted by the weight by thousands of feet of 
thickness, and its carrying powers when in motion, by which 
it transports rocky débris hundreds of miles and deposits it 
in these hillocks. Visions such as these, suggested by the 
environments of the lakes, contrast finely with those derived 
from the life-remains found in these lake marls, silts, or 
peats, glimpses of quiet lakes in which the liveliest life is 
that of the pond shail (Limnea), or of the water fleas 
(Ostracoda),—the one creeping slowly along the surtace of the 
water at its proverbial pace, the other darting through it in 
little leaps, or nibbling the green conferve on the leaves or 
stems of pond weeds; or the still quieter life of the lake peat 
period represented by the seeds found in them, which tell 
only of vegetable growth which the eye cannot detect, and 
we only know by a comparison of now and then. 
From these remarks an idea may be had of the object. of 
this paper. It is intended to give brief notices of the 
localities and positions from which the lake marls, silts, or 
peats were obtained, and then either separate lists or a 
general list of the Mollusca and, Ostracoda found in each. 
The notices will necessarily be brief, and confined mainly to 
the acquirement of the silts or marls, without any lenethened 
or detailed statement of the circumstances under which each 
was deposited. . But in one case—that of the marl from the 
Meadows—we have a description of the lake deposits, and of 
‘the manner of their deposition, so far exceeding any we can 
of our own knowledge give, that a summary of it may be 
given, referring those who wish for further details to “Edin- 
burgh and its Neighbourhood,” by Hugh Miller, pages 6-10 
and 134-147. Mr Miller tells us that in 1842 the Meadows— 
