352 



CRUSTACEA. 



The following are all the species of Trilobites known in the Calciferous 

 formation in Canada up to the present time : — 



Fig. 338. 



Fig. 339. 



Fig. 340. 



Pig. 338. — Dolichometopus ? rarus. 



339. — Jlmj)hion Salteril enlarged two diameters. 



340.. — fisaphus canalis 1 



341. — n, Bathyurns amplimar^inatus ; b, B. conicui ; c, B. Cijhele. 



Remarks. — The specimen of A. canalis above figured appears to me 

 to be perfectly identical with those that occur in Newfoundland and the 

 localities mentioned on p. 270. It was found in the Calciferous formation 

 near IMirrickville by Mr. Francis Ballantyne, of the Township of Kitley. 



The pygidium above referred to Amphion Salteri, cannot be distin- 

 guished specifically from the original specimen on which the species was 

 founded. It was collected in the Calciferous formation in the Township 

 of O.xford, by T. C. Weston. This species was first discovered by J. 

 Richardson in the limestone of the Quebec group at Phillipsburgh. 



Dolichometopus? rarus differs from D. convexus (^ante, p. 269), in 

 having the axis of the pygidium somewhat shorter, and having only two 

 simple grooves in the side lobes. D. gibberulus (p. 269) has a shorter 

 axis, which is smooth. These three species are certainly very closely 



