229 



1854. Sphcerophthalmus alatus, Ang. Pal. Scand., p. 49, t. xxvi, fig. 9. 

 1866. Olenus (Sphcerophthalmus) humilis, Salt., Mem. Geol. Surv. G. 



Brit., vol. iii, p. 302, t. v., fig. 12. 

 1880. Sphcerophthalmus alatus, Linrs. Geol. forening i Stockholm For- 



handl, No. 60 ; Bd. v., No. 4, p. 7, t. 1, fig! 6-10. 

 1893. S. alatus var. Canadensis, Trans. Roy. Soc. Can., vol. xi., p. 107, 



pi. 17, figs. 11 a and b. 



This common and widespread species of the Upper Cambrian has been 

 found at two points in the eastern provinces of Canada, viz., at St. John, 

 N.B., and at McNeill brook, near the Mira river in Cape Breton. It is 

 found both in the dark gray slates at the latter locality and in some of 

 the thin limestone bands found in these slates. 



The Cape Breton material is not sufficient to determine whether the 

 variety is represented there, or the original form. 



CTENOPYGE, Linrs. 1880. 

 CTEXOPYGE PECTEX, Salter. PI. XVII., Figs. 5 a and b. 



1864. Olenus (Sphcerophthalmus) pecten, Salt. Mem. Geol. Surv. G. Ctenopyge 



Brit., Dec. xi., p. 9, t. viii., fig. 11, 13. 

 1866. Olenus (Sphcerophthalmus) Jlagillifer, Salt. Mem. Geol. Surv. G. 



Brit., vol. iii, p. 301, t. 5, figs. 3, 9. 

 1866. Olenus (Sphcerophthalmus) alatus, Salt. Loc. cit., p. 302, t. 4., 



fig. 3, 3a. 

 1891. Ctenopyge pecten, Trans. Roy. Soc. Can., vol. ix., p. 58. 



This species, which was only doubtfully recognized by fragments in the 

 limestone lintels of the black slates of Div. C. 3b, at King street, St. 

 John, is clearly present in the corresponding assise in Cape Breton. The 

 peculiar herring-bone-like rachis of its broad pygidium is frequently met 

 with among other fossils of this horizon on the Escasonie shore. Linnar- 

 sson asserts that the segment of the side lobes in this pygidium are quite 

 free from each other, and are entirely analagous to the pleurae of the 

 thorax ; yet the rachis must be strongly cemented, for it is a part not 

 infrequently met with when no other portion of the pygidium can be 

 recognized. This, we may assume, is owing to the fact that the almost 

 free lateral segments have, owing to their slenderness, been broken off- 

 A rough copy of Linnarsson's beautiful figure is reproduced on one of the 

 plates with article PL xvn., fig. 5 b. 



This species is quite abundantly mingled with Sphcerophthalmus Fletcheri Occurs with 

 on surfaces of the bituminous limestone at the Escasonie shore. Most of 



