CANADIAN PALAEOZOIC CORALS. 11 



Pavosites hemispherica, Milne-Edwards and Haime. (Sp.) 



Favosites alveolaris, Hall. 1843. Geol. of New York, p. 157, No. 13, figs. 1, la. 

 Emmonsia hemispherica, Milne-Edwards and Haime. 1851. Polyp. !Fosb. des Terr. 

 Palseoz., p. 247. 

 H 11 Milne-Edwards and Haime. 1853. Brit. Foss. Corals, p. 



218, pi. XL VIII., figs. 4, 4a. 

 Calamopora hemispherica Rominger. 1862. Am. Jour. Sci. and Arts, 2nd Series, vol. 



XXXIV., p. 394. 

 Favosites hemispherica Billings. 1859. Canadian Journal, new series, vol. IV., p. 

 105, figs. 5, 6, 7. 

 II 11 Nicholson. 1874. Palseon. of Ont., p. 49, pi. VIII., fig. 3. 



Favosites (Emmonsia) hemispherica, Nicholson. 1879. Palseoz. Tab. Corals, p. 67, 



fig. 15, pi. III., figs., 3, 3a, 36. 

 Favosites Bmm/msii, Rominger. 1876. Geol. Sur. Mich., Foss. Corals, p. 26, pi. VII., 

 figs. 1, 2. 

 t. 1. Hall. 1876. Illus. Dev. Foss., pi. IX., figs. 1—6; pi. XI, fig. 



5; pi. XII., figs. 1—5. 

 Favosites hemisphcerioa, Whiteaves. 1889. Contr. to Can. Palseon., vol. I., pt. II, 

 p. 121. 



Corallum forming large masses, sometimes nearly 1 foot across and 

 over 4 inches in thickness or height. Corallites prismatic, rather un- 

 equal in size, varying from 1 to 2'5 mm. in diameter in the same speci- 

 men. Pores with raised margins, in one, two or three rows in the sides 

 of the walls of the corallities, placed close together ; about -2 mm. in dia- 

 meter and '50 mm. apart. Tabulse apparently absent. Squamulse very 

 numerous, one above each pore, reaching to and often past the centre of 

 the corallites, frequently inosculating, thin at the edge with strong 

 bases, about "50 mm. apart vertically and often inclined slightly upward 

 or downward ; those of one row generally alternating and interlocking 

 with those of another. 



Complete tabulae seem to be wanting, but as in Favosites basaltica the 

 union of several squamulse, on about the same level, may result in the 

 production of an undulating and rather imperfect partition across the 

 corallite. 



This species differs from F. basaltica, Goldfuss, in the apparent 

 absence of true tabulse and in the somewhat more numerous squamulse, 

 although if a comparison be made with some specimens of F. basaltica 

 in which the pores and squamulse are abundant, the difference is seen to 

 be so slight as to make it doubtful whether F. hemispherica is really 

 distinct from F. basaltica ; perhaps it would be better to regard it 

 rather as a variety of basaltica than as a distinct species. In 1859, in 

 the Canadian Journal, vol. IV., p. 108, Mr. Billings expressed a doubt 

 as to whether the two species are really separable. 



Occurs in the Corniferous limestone of Ontario. 



