14 The Irish Naturalist. [January, 



THE PAI^^ONTOGRAPHICAI. SOCIETY IN IRELAND. 



lYIonoerraph of the Carboniferous Cephalopoda of Ireland. 



By Arthur II. Foord, Ph.D. (Munch.), F.G.S. Part i. Family 

 Orthoceratidic {\\\ Part), pp. i-22 ; pis. i.-vii., 1897. Part ii. Containing 

 the laniilies Orthoccratidic (concluding part), Actinoceratidie^ Cyrto- 

 icratidce, and Pott'riocc'ratidti\\>-^. 23-48 ; pis. viii.-xvii., 1898. Palseonto- 

 graphical Society. 



In view of the possibility of establishing life-zones in the Carboniferous 

 rocks it is necessary that the organic remains should be minutely 

 described and accurately figured. Everyone specially interested in these 

 rocks has felt the want of satisfactory figures and descriptions of the 

 Cephalopoda and will therefore, we are sure, heartily welcome Dr. 

 Fooid's Monograph, which is appearing in the publications of the 

 Pala;ontographical vSociety. Having previously worked through all the 

 Nautiloidea in the British Museum collection, which contains a number 

 of Sowerby's and of Phillips's type-specimens, Dr. Foord was eminently 

 fitted to undertake such a Monograph. The two parts which have 

 already appeared include the straight or only slightly curved Nautiloids, 

 viz., Orthoccras. Acdnoccras^ Cyrtoccras.Wx^ new genus Eusthe}ioceras,^n(\. Potcrio- 

 cents. The importance of the work will beat once apparent when it is 

 stated that of the twenty-seven species of Orlhoceras that are described, 

 twenty are due to the author's researches, and are here figured for the first 

 time in the admirable manner so characteristic of the publications of the 

 Palseontographical Societ}-. The differentiation of these comparatively 

 straight forms is particularly difficult owing to the paucity of the specific 

 characters, these being chiefl3-the rate of tapering, the shape of the 

 transverse section, the form of the septa, the position and character of 

 the siphuncle, and the nature of the ornaments of the test. New species of 

 Aiti'noceras^ of Cyrtoceras, and of Fofcrioicras are also described and figured. 

 F'or the species from Oldtown, Queen's County, that De Koninck figured 

 and described under the name Cyrtoceras Hitlli. J)r. Foord proposes the 

 new genus Eusthcnoceras^ a genus possessing characters which are inter- 

 mediate between those of Ort/wccras, and those of Me/oceras, a subgenus of 

 Cyrtoceras. Apparently the species is not very rare, and according to the 

 author " the great size of the individuals belonging to this species is 

 worthy of note, and did not escape De Koninck's attention in his descrip- 

 tion of the species. There were giants in those days in the Carboniferous 

 seas of the British and Belgian areas ; this may at least be said of the 

 Cephalopoda, for not onh' did Actinoceras gigantetim flourish and abound, 

 but there were also gigantic forms of many of the coiled shells . . . 

 Favourable environments, immunity from the attacks of their enemies, 

 and other physical conditions may be invoked to account for such unusual 

 development whicli was most marked in the Irish area. ' Although 

 departing in same particulars from E, HuI//\ Dr. I'oord places provisionally 

 in this genus the unique specimen from Samphire Island, in the County 

 of Kerry, that De Koninck described as Cyrtoceras Bailyi. We heartily 



