6 CONTRIBUTIONS TO CANADIAN PALEONTOLOGY. 



maximum thickness or height and is a portion only of the entire 

 corallum. 



Specimens of Favosites aspera were collected in the Silurian (Niagara) 

 near the mouth of the Saskatchewan River at Roche Rouge by J. B. 

 Tyrrell in 1890, and a little lower down the river at Grand Rapids by 

 D. B. Dow ling in 1891 ; also in the Cambro-Silurian at a locality 

 (station 1030) a few miles south of Long Point, Lake Winnipeg, by D. B. 

 Dowling in 1891. 



Favosites Hisingeri, Milne-Edwards and Haime. 



Favosites Hisingeri, Milne-Edwards and Haime. 1851. Potyp. Fobs. desTerr. Palaeoz., 



p. 240, pi. XVII., figs. 2, 2a, 26. 

 Astrocerium venustum, Hall. 1852. Palaeon. New York, vol. II., p. 120, pi. 34, 



figs, la— j. 

 Astrocerium parasiticum, Hall. 1852. Ibid, p. 122, pi. 34, figs. 2a— i. 

 Astrocerium pyriforme, Hall. 1852. Ibid, p. 123, pi. 34 A, figs, la — e. 

 Favosites Hisingeri, Milne-Edwards and Haime, 1855. Brit. Foss. Corals, p. 259, pi. 61, 



figs. 1, la, lb. 

 Calarnopora venusta, Rominger. 1862. Am. Jour. Sci. and Arts, 2nd series, vol. 



XXXIV., p. 394. 

 Favosites venusta, Nicholson. 1875. Palaeon. of Ont., pp. 52 and 65. 

 Favosites venusttis, Kominger. 1876. Geol. Sur. Mich., Foss. Corals, p. 22, pi. V, fig. 3. 

 Favosites Hisingeri, Whiteaves. 1895. Palaeoz. Foss., vol. III., pt. II., p. 51. 

 Astrocerium venustum, Whitfield. 1882. Geol. of Wisconsin, vol. IV., p. 270, pi. 

 XIII., figs. 8, 9, 10. 



Corallum forming massive expansions of irregular shape, attaining a 

 considerable size but seldom more than 2 or 3 inches in thickness ; 

 lower surface protected by an epitheca. Corallites prismatic, small, 

 varying in diameter from '5 to 1 • 5 mm. across in the same specimen. 

 Septal spines numerous, sharply pointed, long, reaching to or almost to 

 the centre of the corallites, generally curved slightly upward and 

 arranged in longitudinal rows, Pores of moderate size, occurring in 

 one or two rows in the sides of the corallites. Tabuke flat, horizontal, 

 about from two to four in a space of 1 mm. 



This species differs from F. Gothlandica in the smallness of its coral- 

 lites and the much greater length of the septal spines ; from F. aspera, 

 in which the septal spines are frequently of considerable length, it is 

 easily recognized hy the pores being placed in the sides instead of at or 

 near the angles of the corallites and by the smaller size of the corallites 

 in average specimens. 



Favosites hispida, Rominger,* is a form which differs from F. Hisingeri, 

 as generally understood, only in a slight increase in the diameter of the 



Geological Survey of Michigan, Fossil Corals, p. 22, pi. V., fig. 4. 1876. 



