Mineralogy and Geology. 3 295 
entire absence of any indications of geological strata so high up in the 
series as the Carboniferous formation. The siliceous pebbles seem to 
have served as gravel for the mortar used in building the houses for car- 
rying on the various objects for which the expedition was sent out. No 
trace of any mineral containing silver existed in the collections. The 
worn by the natives was found to be lead. Tuos. Eeie TON. 
But little attention was paid to zoology, Mr. Hall not having the 
means at hand for the preservation of specimens. A single specimen of 
pyriformis Rathke, an Ascidian mollusk, originally found on the coast of 
Norway.” Only two species of birds were brought, viz: Colymbus tor- 
quatus Brunwich, and Plectrophanes nivalis Linn. 
mammals, he obtained two Lemming’ which were referred for de- 
termination to Prof. S. F. Baird of the Smithsonian Institution. He 
informs me that they agree best with Georychus helvolus Audubon, and 
® should so consider them for the present. | Gzo. N. Lawrence. 
Jou 
from the Blue Limestone of Cincinnati, by G. Granam, J. G. ANTHONY 
dU. P. Jamas, illustrated by a figure from a drawing by the last-men- 
tioned. In a recent letter from Mr. James, the writer learns that the 
. bee So 
to it, Deriving the name from the true discoverer, the species will then 
ere amesit 
modern Limulus : 
The shield is three times as broad as long, has a strong thickened border, 
rounded lateral angles, and small but quite prominent eyes. 
ents h i 
a one is a straight spine, which may have been, Prof. Hall obse 
ag spine of this species. is 
ites, found in the Potsdam sandstone of Canada by Logan, may 
: Proceedings of the Portland Society of Natural History, vol. i, 
Patt 1—This volume of 100 octavo pages is the first publication, in 
