126 Prof. H. A. Nicholson’s Contributions 
I think it tolerably certain that this form corresponds with 
part of the Favosites jibrosa of Mr. Lonsdale (Sil. Syst. 
pl. xv. dis, figs. 6-6 d); and I should very willingly have 
retained the specific name of fibrosa if this had seemed at all 
advisable. The name of Favosites fibrosa has, however, been 
given by different authors to very different corals *, and the 
specific name can only be retained for the form to which Gold- 
fuss originally applied this title, whatever that may really be. 
The widest differences also have existed among British pale- 
optologists in their descriptions of the characters and structure 
of the forms to which this name has been given. Thus Mr. 
Lonsdale both figures and describes mural pores in some of 
the forms which he placed under Favosites fibrosa, whereas 
M‘Coy expresses his conviction that mural pores are wanting, 
and places the forms which he considers Lonsdale to have 
had in view under Stenopora, retaining for them the specific 
name of Goldfuss. Again, it seems certain that Milne- 
Edwards and Haime, in their great work on the British 
Fossil Corals, included two quite distinct types, one from the 
Devonian and the other from the Silurian, under the name of 
Favosites fibrosa. Upon the whole, therefore, it has appeared 
to me to be safest to give a new name to the forms now 
under consideration, even though they should prove to be 
what Lonsdale regarded as Havosites fibrosa, Goldf. 
As to the generic position of this type, I have failed to 
convince myself that it possesses mural pores. ‘The shape of 
the tubes reminds one of what one sees in some species of 
Favosites, such as I. aspera, D’Orb., and £. mullochensis, 
Nich. and Eth., and one naturally expects to find foramina 
on the crenulated angles of the corallites. Moreover, I have 
occasionally seen phenomena which I should have regarded as 
probably indicating the presence of mural pores, had I been 
able to look only at rough fractures of the coral with a com- 
paratively low magnifying-power. If mural pores really 
* If we take the description of Favosies fibrosa, Goldf., given by Milne- 
Edwards & Haime (Pol. Foss. p. 244) we tind at once that it cannot 
possibly be the same as the form here under consideration, since (quite 
apart from the question of the presence or absence of mural pores) the 
tabulee are stated to be very close-set (five or six in the space of a milli- 
metre). Similarly the close-set tabulz, as well as the want of crenulated 
corallites, will show that the form figured by these same authors from 
the Devonian of Devonshire as F. fibrosa, Goldf. (Brit. Foss. Cor. pl. xlviii. 
figs. 3-36), cannot be identical with the present type. On the other 
hand, the coral figured by Milne-Edwards and Haime under the same 
name from the Upper Silurian of Britain (Brit. Foss. Cor. pl. lxi. figs. 5, 
5a) does really seem to be identical with the form which I have here 
described. 
ee 
