DEVONIAN ROCKS OF CANADA WEST. 99 



Genus Favosites (Lamarck). 



Generic Characters. — Corallum dendroid, or forming pyriform con- 

 vex or depressed hemispherical masses, composed of polygonal slender 

 corallites, which are divided transversely into numerous compartments- 

 by complete or incomplete diaphragms. Walls, with one or more 

 rows of circular pores forming communications between contiguous 

 cells. Radiating septa, represented by series of small tubercles or 

 short spines. 



The genera Emmonsia, of Edwards and Haime^ and Astrocerium, 

 Hall, appear to be identical with Favosites. 



Favosites Gothlandica (Lamarck), 



This species, which no doubt should be regarded as the type of the 

 genus Favosites, was established, as its name implies, upon specimens 

 procured from the island of Gothland, in the Baltic Sea, where it 

 occurs in a coralline limestone, that is known to be the equivalent of 

 the Wenlock rocks of England, and of the Niagara group on this 

 continent. Although more abundant, and more often quoted by 

 geologists, than any other species, yet we know of no palseozoic coral 

 concerning which there exists so great a diversity of opinion. Indeed, 

 so variously has it been defined by the best authors, that, without 

 much comparison and fusing of differences, it is hardly possible t» 

 show that it includes any of our Devonian specimens. The following 

 are the descriptions of several of the leading palseontologists : 



1st. GoLDFUss. Petrefacta Germanice, Vol, I., p. 78 ; PL 26, Fig. 



3 a, 3 b, 3 c, 3 d, 3 e, 4 d, 4 c. 



This distinguished author describes the species as being globular or 

 placentiform, with prismatic tubes either sub-equal or with smaller 

 ones interposed ; transverse diaphragms flat ; communicating pores in 

 two rows. 



He does not give any measurements, and we are therefore obliged 

 to rely upon his figures for the dimensions of the tubes. They are as 

 follows :— In fig 3 a, which is generally admitted to be a very charac- 

 teristic form of the species, the tubes are, upon an average, one and a 

 half lines in diameter, some of them being two lines and others only 

 one hne. This is important, because, as we shall see hereafter, the 

 species is described by several palaeontologists as having the cells only 

 one line wide, upon an average. In this figure two rows of pores are 

 represented, those of the same series being distant from each other 



