ON THE SPECIES OF 



FAVOSITES OF THE DEVONIAN ROCKS OF 

 WESTERN ONTARIO* 



BT H. ALLBYNE NICHOLSON, M.D., D. Sc, M.A., F.R.S.E., 



Professor of Natural I^story in TTniversity College, Toronto. 



Those who are acquainted with the subject will not need to be told 

 that the present communication is to a large extent simply supple- 

 mentary to the admirable paper published by Mr. Billings upon the 

 Devonian Corals of Canada West, in which the species of Favosites 

 are treated at considerable length (Canadian Journal, New Series, 

 Vol. iv. p. 97). In some respects I find myself unable to agree with 

 this eminent palaeontologist in the conclusions at which he has arrived j 

 and as I have had the opportunity of carefully examining a very 

 extensive series of specimens, I am induced to submit my views upon 

 this very perplexing group of corals. 



The gentis Favosites, Lamarck, comprises branched or massive 

 corals, composed of numerous more or less polygonal corallites, which 

 are divided internally by transverse septa or " tabulse," sometimes 

 quite rudimentary. The walls of the corallites are perforated by one, 

 two, three, or more rows of " mural pores," by which the separate 

 corallites are placed in communication. The septa are absent or 

 rudimentary, being at most represented by tubercles or short spines. 



The generic limits of Favosites have not been universally agreed 

 upon by palaeontologists, and the genera Emmonsia, Edw. & H., and 

 Astroceriuni, Hall, have been founded upon differences which Mr. 



* As the present communication will be published, in a somewhat enlarged form, in a Report 

 which I am preparing upon the organic remains of certain of the Palaeozoic formations of 

 Ontario, I have not in the meanwhile thought it necessary to prepare illustrations of the species, 

 therein described. 



