THE HAMILTON ASSOCIATION. 113 
it was useless to send it to Dr. Whiteaves, Ottawa. This was 
merely one of several cases known to me where the National 
Museum lost specimens which we may find some difficulty in 
replacing. 
Few unknown fossils turned up during the past summer 
along the lake shore. Some, however, are of “ the interesting 
finds.” A fine example of the Hudson River (Bala) Lamelli- 
branch, Modiolopsis Modiolaris. Hale displays a portion of 
the outer shell, in a fossilized state, the lines of growth are 
well marked grooves. Internal casts of single and double 
valves are quite common in the Drift here, but this peculiarity 
may be recorded.* It may have attracted the attention of 
Palzantologists elsewhere, but the thin shell was unnoticed 
hitherto among scores collected by the writer and other mem- 
bers of the Geological Section here. True, faint concentric 
lines of growth are found on casts of Modiolopsis Concentrica 
occasionally. Perhaps all the Lamelli-branches of this group 
were provided with very thin shells. In the Palzeontology of 
Ontario, by Professor H. T. Nicholson, under the head, Chap- 
ter I]. Fossils of “The Hudson River Formation,” you will 
find a figure of ‘ Modtolopsis Curta”’ (Hall) in which fine 
concentric lines are represented. . These do not appear in the 
Hudson River casts (Drift) here. Perhaps the matrix in 
which they are embedded, limestone was not favorable for their 
preservation. The Cyrtodontas (3) were discovered in some 
of the most unpromising slabs one could select. 
Our fellow-worker, Mr. Bartlett, has been successful in ob- 
taining from the Cambro-Silurian Drift some interesting speci- 
mens not found by myself or others here hitherto, which we 
may add to the list already published, namely the handsome 
gasteropod, “ Cyclonema Vilex,’ Conrad, U. 5. A. (also occurs 
in, Anticosta), and a Brachiopod, which appears to be “ Glos- 
sina T'rentonensis—Con.” The fragments of a minute Ortho- 
ceras, resembling a long narrow tube, I have not seen figured ; 
a New species probably. 
*Note—These lines I find were figured by Sir W. Logan already. 
