GENERA OF FAVOSITID.E. 171 



America. I have never myself been so fortunate as to meet 

 with any specimens which I could refer without doubt to 

 Favosites fibrosa, Goldf. sp., as defined by the eminent French 

 authors above referred to ; and I am therefore quite unable 

 to express any opinion as to its affinities. It seems, however, 

 quite certain that the corals described by Professor M'Coy 

 under the name of Stawpora fibrosa, Goldf. sp., have in reality 

 no relations whatever with the true Stenopora of Lonsdale. On 

 the contrary, it is almost certain that they belong to the genus 

 Chcstetes, Fischer, or to Montindipora, D'Orb., as ordinarily 

 understood ; and the same may be pretty confidently asserted 

 of all the examples of Stenopora which have subsequently been 

 quoted by various writers as occurring in the Silurian deposits 

 of various parts of the world. At the same time, though I 

 think that we have at present no actual evidence of the exist- 

 ence of any species of Stenopora in the Silurian rocks, it is 

 quite possible that a more extended investigation may yet 

 show some of the so-called MonticnliporcB of the Silurian to be 

 really referable to the former genus. We shall subsequently 

 see, indeed, that there are certain of the Silurian Monticuli- 

 porce which, except in the apparent absence of " mural pores," 

 make a very close approach in structure to Stenopora. 



It is quite clear, further, that with the available information 

 as to the structure of the genus Stenopora, Lonsd., it was im- 

 possible to establish any satisfactory generic distinction between 

 this type and Chcetetes or Montiailipora ; and this view was the 

 one finally adopted by Milne-Edwards and Haime, and subse- 

 quently followed by myself (Quart. Journ. Geol. Soc, vol. xxx. 

 p. 499, 1874). To this opinion I should have been still in- 

 clined to adhere; but Professor De Koninck has shown that 

 one of the species described by Lonsdale (viz., S. ovata) pos- 

 sesses perforated walls, and is therefore fundamentally separ- 

 ated from the entire family of the Chcetetidce. Indeed he refers 

 the species just mentioned to the genus Favosites itself. I have, 

 moreover, recently had the opportunity of examining a tolerably 

 extensive series of examples of Stenopora, mosdy collected by 



