56 TABULATE CORALS. 



are compared together. To the supposed peculiarities in its 

 mode of growth, I think no weight can be attached, as F. GotJi- 

 landica has commonly a similar habit ; and there are no other 

 points of separation worth alluding to. Upon the whole, after 

 minutely examining F. Billingsii, in the ordinary manner and 

 by means of microscopic sections, I cannot consider it as more 

 than varietally distinct from F. Gothlandica, of which it may 

 be regarded as a local variation. 



Formation and Locality} — Upper Silurian (Wenlock Lime- 

 stone), Dudley and Benthall Edge; also near Shalloch Mill, Gir- 

 van. Wenlock Limestone, Gotland. Niagara Group (Wenlock 

 Limestone), Owen's Sound and Manitoulin Island, Ontario. 

 Guelph Formation (Upper Silurian), Cedarville, Ohio. Corni- 

 ferous Limestone (Devonian), Port Colborne, Woodstock, and 

 various other localities in Ontario ; also in the same formation, 

 Phelps, State of New York. Hamilton Formation (Devonian), 

 Erie Co., State of New York, and Arkona, Ontario (var. Bil- 

 lingsii, Rom.) The species is quoted by Milne-Edwards and 

 Haime from the Caradoc sandstone of Britain (Mon. Brit. Foss. 

 Con, p. 257) ; but I have never seen any example from strata 

 of Lower Silurian age. It is generally regarded as one of the 

 most abundant and characteristic of the Upper Silurian Corals ; 

 but my own experience would, so far as it goes, be in favour of 

 considering F. Forbesi, E. and H., as by far the commoner of 

 the two in the Upper Silurian of Britain, while F. Gothlandica 

 appears to attain its maximum in the Devonian. 



Favosites Forbesi, Edwards and Haime. 

 (PL I., fig. 7; PI. IL, figs. 1-3 ; PI. III., figs. I, 2.) 



Calamopora basaltka (pars), Goldfuss, Petref. Germ., vol. i. p. 78, tab. xxvi., 



figs. 4 « -4 1^, 1829. 

 Favosites Gotltlandica, Lonsdale, in Murchison's Silurian System, p. 682, PI. 



XV., bis, figs. 3, 4, 1839. 

 ., Forbesi, Milne - Edwards and Jules Haime, Pol. Foss. des Terr. 



Pal., p. 238, 1851. 



1 Under this heading I shall, as a rule, only give those localities from which I 

 ni}self possess specimens. When this rule is departed from, the name of tlie author 

 on whose authority the reference is given will be appended in brackets. 



