116 Geological Society . 
stems, like some now forming in the alluvial mud of the St. 
Lawrence. 
Some curious combinations of worm-tracks with ripple-marks and 
shrinkage-tracks are described ; as also branching or radiating 
worm-trails, which present some resemblance to branching Fucoids. 
Finally, the Author describes the formation of rill-marks on the 
mud-banks of the tidal estuaries of the Bay of Fundy, and indicates 
their identity with some impressions in slabs of rock which have 
been described as Fucoids under several generic names. 
May 21, 1890.— Dr. A. Geikie, F.E.S., 
President, in the Chair. 
The following communications were read : — 
1. “ On some Devonian and Silurian Ostracoda from North 
America, France, and the Bosphorus.” By Prof. T. Bupert Jones, 
F.B.S., F.G.S. 
Of the Devonian species herein figured and described, six species 
and one variety (four being new) from the decomposed Chert of the 
Corniferous Limestone of Ontario County, in the State of New York, 
and new species from the Hamilton Group of Clarke Co., Indiana, 
have been sent by Mr. J. M. Clarke, of Albany, N. Y., as mentioned 
in the February number of the Quart. Journ. Geol. Soc. p. 14. 
From Eighteen-mile Creek, Lake Erie, N. Y., there are two new 
Devonian species among specimens supplied by Dr. Hinde (op. cit. 
p. 28), and two new Primitice from Thedford. Altogether five 
genera (Bollia, J. & H., Mooreci , J. & K., Octonaria, J., Eurychilina , 
Ulrich, and Ulrichia , gen. nov.) are hereby added to the list of 
“ Hamilton 99 fossils. 
The Devonian Beyrichia collected some years ago by M. Dumont 
at the Bosphorus, and noticed by Dr. Ferd. Homer in the 6 Neues 
Jafirbuch’ for 1863, having been kindly lent by M. Dewalque for 
examination, is figured and described in detail. It appears to be 
the same as B. devonica , Jones, lately described from Devonshire. 
Nine new species from Anticosti, in Dr. Hinde’s collection, 
alluded to above, are here figured and described. They are from 
Mr. Billings's “ Anticosti Group ” (Divisions 3, 2, 1, and the lowest). 
The lowest and Div. 1 are both now regarded as of Lower Silurian 
age, and Divs. 2 and 3 are either Middle or Upper Silurian. A 
series of Silurian Ostracoda from Canada, submitted by Mr.Whiteaves, 
F.G.S., and Mr. Ami, F.G.S., have been examined, and critical notes 
on them are here given. 
The Lower-Silurian Beyricha Guilleri , named and compared with 
other species by M. G. de Tromelin at Nantes in 1875, who found 
it at Domfront and elsewhere in Brittany, is ako figured and 
described in detail. 
