126 CARBONIFEROUS CEPHALOPODA OF IRELAND. 



Remarhs. — This species is only known to me from Clane, in the county of 

 Kildare, and from Rathkeale, near the town of Limerick ; but its presence in other 

 localities in Ireland may very probably be demonstrated when the search for fossils 

 becomes more systematic and wide-spread thronghont the country. The quarries 

 at Clane have yielded several specimens, whose aggregate features furnish all the 

 data necessary for the full description of the species. 



Localities. — Clane, county of Kildare ; Rathkeale, near Limerick, 



Genus Solenooheilus, Meek and Wurthen, 1870 (emend. Hi/atf, 1883, 1893). 

 SoLENOCHEiLUS DOHsALis, /. PhilUjjs, sp. Plates XXXIII, XXXIV. 



1836. Nautilus dorsalis, J. Phillips. Geology of Yorkshire, pt. 2, p. 231, 



? pi. xvii, fig. 17 ; pi. xviii, figs. 1, 2. 

 1843. — — J. E. Portlock. Geology of Loiidouderry, p. 405. 



1849. Chtptoceras dorsalis, A. cV Orhignxj . Prodr. de Paleout. Stratigr., vol. i, 



(). 114. 



1875. Nautilus dorsalis, W. H. Baihj. Characteristic British Fossils, p. 117, 



pi. xl, fig. 7. 



1876. — — Armstronr/, Young, and Boherfson. Catalogue of 



Western Scottish Fossils, p. 59. 

 1883. AsTMPTOCEEAS DOBSALE, A. Hrjatt. Genera of Fossil Cephalopod.s. 



Proceed. Boston Soc. Nat. Hist., 

 vol. xxii, p. 297 (foot-note). 

 1891. SoLENOCHEiLus DORSALIS, A. H. Foord. Cat. Foss. Ceph. Briti>h 



Museum, pt. 2, p. 169, fig. 27 

 (p. 166) — type specimen. 

 1893. — — A. Hyatt. Carboniferous Cephalopods. 



Second paper. Geological Survey of 

 Texas, Fourth Annual Eeport, 1892, 

 p. 4G0. 

 [Not 1878. Nautilus dorsalis, L. G. de Koninck. Faune Calc. Carb. Belg. (Ann. Mus. Euv. 

 d'Hist. Nat. Belg., torn, ii), p. Ill, pi. xxviii, figs. 1—3. (? var. y of Phillips.)] 



Description. — Shell large, nautilus-like, subglobose, consisting of about two 

 rapidly enlarging involute whorls, the last overlapping the preceding one to the 

 extent of about two-thirds. Umbilicus proportionately small, exposing the inner 

 whorl, having a small central vacuity ; the sides steep, witli rounded margins 

 which are merged in the sides of the shell. The section is broadly sagittate, the 

 periphery forming the apex of the triangle. 



The body-chamber is large, extending to about two-thirds of the circumference 

 of the whorl. The periphery is somewhat narrowly rounded, the sides diverging 

 outwardly from it, very slightly in the first whorl, but much more strongly in the 



