270 Scientific Intelligence. 
closed with a concise summary of the geological range of the 
families and genera. 
The more important genera are concisely described, and a large 
number of less prominent genera are named in their proper places 
with their geological position. The German edition, which has 
already appeared, is to be followed soon, it is announced, by an 
edition in English. H. S. W. 
4. The occurrence of Tertiary clay on Long Island, N. Y. ; 
by Arruur. M. Epwarps, M.D., Newark, N. J. (Communicated.) 
I wish to record the finding of Tertiary clay at Rockaway, Long 
Island, N. Y. ‘Tertiary rock or at least clay was expected to be 
found on the Atlantic shore of Long Island. It was searched for 
on Staten Island without results. The clay found was white, at 
Arrochar, and was identified as Cretaceous by the shells in it. 
But the Tertiary above that was looked for in vain, although 
it may be found there. But on Sunday, 11th of August, 1895, I 
visited Rockaway to study the geology. I saw the moraine of 
the glacial period strongly marked in three hills just beyond 
Brooklyn Hills station; on the top and overlying the glacial drift 
was a coating of glacial clay having fresh-water Bacillariaceze 
(Diatomaceze) in it, the same as I found in New Jersey. The 
hills ended here and the rest was flat until beyond Aqueduct 
station. No opening was made, but I think that Cretaceous clay 
is under the glacial drift. At Aqueduct station the salt water 
begins and the cars run out on tressel works to Rockaway, where 
is a sandy bar. At one place, where they have been digging 
a ditch and recovering the land from the sea, on the opposite side 
of Rockaway to the Atlantic Ocean, some of the soil has been 
dug up. On the top is the Bacillarian clay, the Champlain 
glacial clay. Below this is the white glacial clay containing 
fresh-water Bacillariaceze, and below this is a dark, coarse clay 
which I took home and examined. It is Tertiary clay having 
marine Bacillariacez. But I should think it is Upper Miocene. 
Lower Miocene and Oligocene are as a rule lighter in color. But 
the shells in it are the same. I wish to record this finding now, as 
it 1s important. 
Newark, N. J., August 8. 
5. On Composite Dikes in Arran.—Professor Jupp has de- 
scribed in the Quarterly Journal of the Geological Society (vol. xlix, 
p. 536) a series of remarkable dikes in the Island of Arran, which 
are excellent examples of the ‘‘ composite” type, already recog- 
nized elsewhere as in Canada and Norway, described by Lawson 
and Vogt respectively. Unlike these last, however, in which the 
differentiation has gone on within the dike itself, the Arran dikes 
belong to a different class, formed by the injection of different 
material into the same fissure. It should be mentioned that 
these dikes are part of the latest ejections of igneous material in 
the British Isles. One of the dikes, that of Cir Mhor, having a 
total breadth between the enclosing granite walls of twenty-four 
feet, shows two exterior brands of augite-andesite (55°8 p. e. 
Si0,), four feet wide; within these is the dike proper consisting 
