114 Proceedings of the Uoyal Irish Academy. 



Glyphioceras (Beyrichoceras) Phillipsii, Foord and Crick, 1897. 



Mr. Crick has kindly identified these specimens for me. The shell 

 attains a fair size, and has an aperture of the same shape as G. reticu- 

 latum. In the adult the margin of the periphery becomes almost 

 angular, with two spiral grooves below it, like the form of G. hilingue. 

 The ornament is not reticulate, but crenulato-striate. It occurs in the 

 Pendlcside series in England. 



Locality — Ireland : Lisdoonvarna, = Horizon of Pondleside series. 



Glyphioceras (Beyrichoceras) spirale, Phillips. PL vi., fig. 8. 



This species has not yet been obtained uncrushcd. It is charac- 

 terized by its ornament of regular spiral lines. The species is an 

 important zonal index. 



Localities — England : The lower Culm of Devon, and the Pendle- 

 side series of the Midlands. Ireland : Loughshinny, co. Dublin ; 

 Summerhill and near Trim, co. Meath ; Killorgiin, co. Kerry ; Beds 

 above the Glyphioceras reticidatum beds, Eoynes Island, = Horizon 

 of Pendleside series. 



Glyphioceras (Beyrichoceras) diadema (?), Beyrich. PI. vi., 

 figs. 9-15. 



This species is somewhat unsatisfactory, and includes a number of 

 forms of very varied appearance. It is of great interest that these 

 forms occur with a similar fauna at Chokier, Belgium, and Lisdoon- 

 varna and Foynes in Ireland, in beds immediately above the Yisean 

 stage of the Carboniferous Limestone. In the adult the shell has a 

 moderately wide umbilicus, transverse parallel ridges which become 

 more and more obsolete with age. In the young the umbilicus is 

 very wide, inclusion almost nil, and the ridges are fewer, stronger, 

 and more acute, and there is an angular keel at each margin of the 

 periphery. At times this condition persists in the adult, and in a 

 large collection many intermediate forms occur. 



Glyphioceras (Beyrichoceras) divaricatum sp. nov. PL vi., fig. 16. 



Specific characters — Shell discoidal; umbilicus small, greatest 

 thickness near the edge of umbilicus ; whorls (? number), inclusion 

 nearly complete. 



The test is ornamented with flattened transverse ribs, separated 

 by narrow sulci, each rib bifurcating a little distance from the umbilicus. 

 These ribs are arched forward in the upper part of the lateral margin. 



