36 



The condition in which this species is most frequently found is in 

 that of not very well preserved casts of the interior of the shell. In 

 such specimens the slight angulation of the periphery and of the centre 

 of the lower side is often nearly or quite obsolete, and the outline of 

 the aperture is subovate, the upper side being less convex than the 

 lower. In two unusually well-preserved fragments of this species 

 from Dui'ham, however, which have most of the test preserved, the 

 aperture is clearly subtriangular or ovately triangular in contour. 



Prof. McCoy states* that there are "no chambers" in shells of the 

 genus Ecculiamphalus, but the present species is occasionally septate. 

 Stoliczka places Ecculiomphalus in the Solaridffi, but its afllnities appear 

 to have been very near to Maclurea. 



CEPHALOPODA. 



Tboohoceras desplainense, McChesney. 

 Plate 5, fig. 5. 



Trochoceras Degplainenm, McChesney. 1859, New Palaeozoic Fosssils, p. 68, pi. 



8, fig. 1. 

 Trochoceras Desplainense, Hall Twentieth Eeg. Rep., p. 359, pi. 16, figs, 



8, 9 and 10. 



Heepeler, T. C. Weston, 1861 : two specimens, one a mould of the 

 exterior of the outer whorl in a compact dolomite, and the other a cast 

 of the interior of part of the body whorl. 



TrOCHOLITES MULTICOSTATtJS. 



Piate 6, figs. 1 and In. 



Lituiles mvUicoslatus, Whitfield. Geol. of "Wise, vol 4. 1882, p. 303, pi. 20, fig. 7. 



Blora, E. Bell, 1861 : Hespeler, T. C. Weston, 1867 and 1871 : Dur- 

 ham, Mr. J. Townsend : six specimens in all. Three imperfect exam- 

 ples of a shell which is probably referable to this species wore collected 

 by T. C. Weston in 186*7, from the Niagara formation at Grimsby, Ont. 



The Z. multicostatus of Whitfield, from the iS iagara formation of 

 Waukesha, Wisconsin, appears to have been described from distorted 

 or abnormally compressed individuals, which did not show the position 



* British Palaeozoio Fossils. Page 301. 



