192 The Ottawa Naturalist. [January 



ton, Ontario, and L. Whitfieldi, Hall, from the Maquoketa (Ordo- 

 vician) ot Iowa, U.S.A. 



/). Orbiculoidea Hartti^ Clarke, a form probably more nearly 

 related to O. ienuilamellata, Hall, than to any other species. 

 Discina Clara, Spencer, from Hamilton, Ont., is placed here as a 

 synonym of Orbiculoidea tenuilamellata, Hall. Schuchert places 

 Discina Clara, Spencer, as a syn. und^r Schizotreta tenuilaynellata. 



5. PJioUdops Trombetana, Clarke. This form recalls to mind 

 the Pholidops implicata, Sowerby. 



6. Or/his ( Dahnanella) Freitana, Clarke, a form resembling 

 Orthis (Dahnanella) eftiacerata, a variation of Orthis testudinaria, 

 Dalman. 



7. Chonefes, sp. cf. C. Nova-Scotica, Hall. 



8. Anoplotheca ( Anabaia ) Paraia, Clarke. 



9. Anabaia Anticostiensis, Clarke. Of this Dr. Clarke writes : 



" By a fortunate incident I have discovered a species from the 

 middle Silurian of Cape East, on the Island of Anticosti, which is 

 very similar to A. Paraia, It possesses valves of the same con- 

 tour lacking the reflection of the margins, which may be accident- 

 ally absent, as the specimens are preserved in limestone ; the 

 peculiar plication of the brachial valves is quite the same, the 

 opposite valve differing only in the presence of a single median 

 plication in the sinus. These specimens have shown a trace of 

 everted oblique internal spires 



The species is without a name, as far as I can ascertain, un- 

 less it be that identified by Mr. Billings as LeptoccBlia hemispherica 

 ( Atrypa hemispherica, Sowerby). That it is not the British 

 species, nor that member of the Clinton fauna of New York, pass- 

 ing under the name of A. hemispherica (Sowerby) Hall, I am con- 

 fident. In order to determine whether it was the form referred to 

 by Mr. Billings, I asked Mr. H. M. Ami, of the Geological Survey 

 of Canada to compare it with the types of the Anticosti species in 

 the collections of the Survey, and this he has kindly done, without 

 finding anything that can be regarded as identical or closely 

 similar. I have given a figure of the Anticosti shell on account of 

 its interesting relations to the Brazilian species, and it may be 



