121 



NOTES ON, AND THE PRECISE GEGLOGTCAL HORIZON 

 OF SIPHONOTRETA SCOTIOA, DAVIDSON. 



BY HENRY M. AMI. 



(A'ead Mai^ch 3nl, 1887.) 



At the Montreal Meeting of the Arafrican Association for the 

 Advancement of Science in 1883, Mr. J. F. Whiteaves, Palfeontologist, 

 &c., to tlie Geological Survey of Canada, read a communication or 

 paper before the Geological Section, in which there was recoi'ded for 

 the first time on tliis continent the occurrence of a beautifully f)"inged, 

 or spinose brachiopod, which, from specimens sent liim, Di\ Thos. 

 Davidson, the eminent autiiority on the Brachiopodii, had recognized 

 to be referable to a form wliich ha himself had described as Si- 

 phonotreta Scotica. Tlie specimens thus referred to de Verneuil's genus 

 Siphonotret'x had been collected by Mr. J. "W. H. Watts, of the Ottawa 

 Field-Naturalists' Club, and that gentleman had handed them to Mr. 

 Whiteaves and sul>sequently presented them to the National Museum 

 at Ottawa where they are now exhibited- in the case. The specimens 

 in question had been obtained from blocks of impure limestone lying 

 near Mr. Watts' residence at Cummings' Bridge, near Ottawa, aiid 

 were said to have come out of a well sunk by the same gentleman on 

 his property. There was but little doubt, both from the lithological 

 aspect of the rock containing the sjiecimens of Siphonotreta and otht-r 

 fossils found an th's property, and from the fades of the included 

 fauna, that the measures whence they came were referable to the Utica 

 Formation. For some time, however, a certain amount of dou'it was 

 entertained by a rinmber of paheontologists as to the precise geological 

 position of the interesting form under consideration ; but, from receftt 

 investigations made with the special object in view of clearing this 

 point, the writer, in conjunction with Mt-ssrs. McConnell, Huyt)er and 

 other member."? of the Ottawa Field-Naturalists' Club has made a 

 number of excursions during^_ which sj'>ecimen3 of this be;iiitiftil .sh^ll 

 were collected. v''^felG/4/ 



