512 Dr. H. A. Nicholson and Mr. A. H. Foord on 



growing in concentric layers measuring as mucli as 8 centim. 

 in breadth and 2 centim. in thickness. Surface monticulose; 

 the monticules conspicuous, from 2 to 3 millim. apart, con- 

 sisting of mesopores. Autopores comparatively large, readily 

 distinguishable by the naked eye. About three of them fill 

 the space of 1 millim. The folds are of average size and 

 occupy about one fourth of the circumference of the walls of 

 the autopores. Acanthopores may be seen in transverse sec- 

 tions at the angles of the walls of the mesopores. Longitu- 

 dinal sections show considerable regularity in the disposition 

 of the vesicular tabulge in the mesopores. The autopores 

 have very few tabulse. 



Ohs. The presence of acanthopores distinguishes Fistu- 

 Upora eriensis from all other species of the genus with the 

 exception of F. ludensis, Nich. (this journal, "p. 119, Feb. 

 1884), from which it is completely separated by its habit of 

 growth and the much larger dimensions of its corallites. The 

 occurrence of acanthopores is in fact the only feature which 

 these two species possess in common. The expression " spi- 

 nuloso-granulose," employed by Dr. Rominger in reference 

 to the surface of this species, no doubt refers to the acantho- 

 pores, which may be visible externally on well-preserved 

 specimens. We have only detected them in transverse 

 sections. 



Formation and Locality. Hamilton Group (Devonian), 

 Canandaigua^ Ontario Co., New York. 



Fistulipora eifeliensis, Schliiter, sp. 



Callojjora eifeliensis, Schliit. Sitzungsbericlite der niederrlieinisclieri 

 Gesellscliaft in Bonn (Physikalische Section), p. 72, Feb. 14, 1881. 



Corallum hemispherical, with a slightly conical base, which 

 may have been furnished with an epitheca. The surface is 

 provided with slightly raised " monticules," upon which 

 there are clusters of the mesopores. In weathered specimens 

 the corallites may be very distinctly made out; they 

 measure about 1^ millim. in their longer diameter by about 

 1 millim. in their shorter. The autopores are irregularly oval 

 or subcircular in outline, and are in general completely iso- 

 lated from each other by the mesopores, but occasionally two 

 come into contact either at their sides or at their extremities. 

 The folds are very small in this species, as may be seen in 

 the section, fig. B. The mesopores vary greatly both in size 

 and in shape ; in some instances four of them encircle an 

 autopore, in others six. 



Longitudinal sections show that the autopores are divided 



