WHiTEAVEs.] DEVONIAN FOSSILS, MACKENZIE RIVER BASIN. 201 



Although Mr. Meek placed this species provisionally in the genus 

 Aulophyllum, he expressly stated that he was quite uncertain whether 

 it ought to be referred to that genus or to Cyathophyllum. On this 

 point his exact words are as follows : — " I know this coral only from 

 fragments less than 0.80 inch in diameter, none of which shew the 

 entire length. They are also nearly all considerably compressed, but 

 this seems to be from accidental pressure. The generic characters can- 

 not be made out with much confidence from such materials, and hence 

 I am by no means satisfied that the species should not be called Cya- 

 thophyllum Richard&oni. As near as its internal structure can be deter- 

 mined, however, from the specimens collected, it would seem to differ 

 from that genus in having an inner wall encircling the central region, 

 and thus more nearly approaching the genus Aulophyllum. It also 

 wants the transverse tabulse generally more or less developed in the 

 central region of Cyathophyllum." 



The specimens upon which Mr. Meek's description was based, which 

 are also from the "Eamparts," have been kindly lent to the present 

 writer, for examination and comparison, by Mr. C. D. Walcott, of the 

 IT. S. Geological Survey. Their internal structure, it may be stated, 

 is in a peculiar and not very good state of preservation. In those of 

 which sections have been made, the appearance of a supposed " inner 

 wall encircling the central region " seems to be due to the fact that 

 the matrix filling uj) the vesicles of a narrow outer zone which cor- 

 responds in breadth to the length of the secondary septa, happens to 

 be of a distinctly darker colour than that which fills up the vesicles of 

 the central portion of the coral. In these and in the much better 

 specimens collected by Mr. McConnell, the writei' has failed to find any 

 indications of an " inner wall " like that of Aulophyllum, and has con- 

 sequently been induced to refer the species to Cyathophyllum. 



In longitudinal sections the specimens obtained by Mr. McConnell 

 shew that from the bottom of the calyx to the base of the coral the 

 primary septa extend to the centre, where they are slightly twisted. 

 There are no tabute proper, but the spaces between all the septa are 

 everyvvhere filled with vesicular tissue, the vesicles being larger and 

 less legular in the central area than they are exteriorly. The most 

 perfect specimen collected, which measures about three inches in 

 length, has its epitheca densely and finely striated acro.ss, in addition 

 to the ordinary surface markings. 



