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 brauching Fiicoids. 

 Pinally, the Author describes the formation of rill-marks on the 

 mud-banks of the tidal estuaries of the Eay of Fundy, and indicates 

 their identity with some imjjressions in slabs of rock which have 

 been described as Fucoids under several generic names. 



May 21, 1890.— Dr. A. Geikie, F.R.S., 

 President, in the Chair. 



The following communications were read : — 



1. " On some Devonian and Silurian Ostracoda from ^Xorth 

 America, France, and the Bospborus." By Prof. T. Eupert Jones, 

 F.R.S., F.G.S. 



Of tho 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, X. 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 s])ecinieiis supplied by Dr. Ilinde (op. cit. 

 p. 28), and two new Primitiir from Thedford. Altogether five 

 •genera (BoUia, J. & H., Moorea, J. & K., Octonaria, J., Eurychilina, 

 Ulrich, and Uh-irJiia, gen, nov.) are hereby added to the list of 

 " Hamilton " fossils. 



The Devonian Bcyrkliia collected some years ago by M. Dumont 

 at the Posphorus, and noticed by I)r. Ferd. Etimcr in the ' Neues 

 Jahrbuch' for 18G3, having been kindly lent by M. Dewalquc 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 lowestX 

 The lowest and Div. 1 are both now regarded as of Lower Silurian 

 age, and Divs. 2 and 3 are either ^liddle or r]>por Silurian. A 

 series of Silurian Ostracoda from Canada, submitted by Mr.AVhiteaves, 

 F.G.S., and ]Mr. Ami, F.G.S., have been examined, and critical notes 

 on them are here given. 



The Lower-Silurian Bo/richa Gidlhri, named and compared with 

 other species by !M. ii. do Tromelin at >"autes in 1875, who found 

 it at Donifront and ehcwbere in ]bitt;iny, is also figured and 

 described in detail. 



