490 General Notes. [June, 
series belong the limonites of the great valley, which occur in 
clays derived from the sub-aérial decay of the rocks, These 
rocks, in their unchanged condition, contain beds and masses of 
siderite and pyrites, the alteration of which 7v set has given rise to 
the limonites. In the formation of this from siderite or iron-car- 
bonate, it was pointed out by the speaker that there is a contract- 
tion of volume equal to about 20 per cent; to which is due the 
cellular character of the limonites and their frequent occurrence 
in the form of geodes. ’ 
_ These older rocks are not without traces of organic life, having 
yielded in the Appalachian valley the original Scolithus, and 
related markings, besides obscure Brachiopods ; and in Ontario, 
besides similar Scolithus like-markings, a form apparently iden- 
tical with the Aozodéu of the more ancient gneisses. may 
hope to find in the Taconian series a fauna which shall help to fill 
the wide interval that now divides that of the Eozoic rocks from 
the Cambrian. We should seek in the study of stratigraphical 
geology not the breaks dividing groups from each other, so muc 
as the beds of passage which serve to unite all these groups 
one great system, remembering that there is no local hiatus which 
is not somewhere filled up by the continuous process of nature-— 
T. Sterry Hunt. 
_ A Fossit PHYLLOPOD CRUSTACEAN FROM THE QUATERNARY 
CLAYS OF CANADA—wWe have received through the kindness of 
Principal J. W. Dawson, LL.D., of Montreal, a valve in partial 
preservation, of an Estheria quite unlike any existing Americal 
form. The following account of its discovery is from Principal 
Dawson: 
“Tt was found at Green’s creek on the Ottawa river, in nodules 
in the Post-pliocene clay, holding skeletons of MJadlotus villosus 
and other northern fishes, and shells of Leda (Portlandia) arcttea, 
Saxicava rugosa, &c.; also leaves of Populus, Potamogeton, &e. 
washed the débris of neighboring land, and of. fresh water streams- 
The climate at the time was colder than at present, and the 
m . 
present some resemblances to £. middendorfit Jones, but- differs me 
the want of anastomosing cross wrinkles between the ridges. = 
One valve and portions of others were preserved; but none 
