Mineralogy and Geology. ce 
gh reddish clay, a few shells of Astarte Laurentiana, and , 
Leda Portlandica, - - =o - - «4 
tay sand, containing detached valves of Saaicava rugosa, 
Mya truncata, and Tellina Grenlandica ; also Trichotropis 
borealis, and Balanus crenatus: the shells in three thin 
_ © layers, - - - - - ais tae . - 
_ Sand and clay, with a few shells, principally Saxicava in de- 
tached valves, - - - - - - - - 
Band of sandy clay, full of Natica clausa, Trichotropis borea- 
lis, Fusus tornatus, Buccinnum undatum, Astarte Lauren- 
tiana, Balanus crenatus, &c. &c., sponges and Foraminifera. 
Nearly all the rare and deep-sea shells of this locality occur 
in this band, - - . - - - a hil 
Sand and clay, a few shells of Astarte and Sacicava, and re- 
mains of sea-weeds with Lepralia attached ; also Foram- 
inifera, - m 
Stony clay, boulder clay. 
It thus appears that at Logan’s farm we have littoral species fi top, 
ie 
deposit. This corresponds precisely with the order observed elsewhere 
in the vicinity of Montreal; though at Logan’s farm the arrangement 1s 
for the first time last 
autumn, At first sight it consists of a mass of stratified sand 
and the underlying boulder clay as usual contains no fossils. My experi 
ence in the Montreal deposits, however, led me to expect a bed, however 
thin, representing the Leda clay, between these ; and on searching at the 
lunction of the two great beds above mentioned, I was gratified by find- 
ing a layer of sand about three inches in thickness, filled with the rarer 
e very spot where 
he surface of the drift. On these stones, 
ting field for observation. In the thin 
that lay on the 
ly imbedded in it, were covered with 
been age on it, represents the 
