i6 Tate — List of Irish Liassic Fossils, 



faint concentric striae. The aperture is not exposed ; but I have no hesitation 

 in referring the shell to the genus Chemnitzia. 



Geological Position — Zone of " A. angulatus," Island Magee, Co. Antrim 

 (S. A. Stewart). 



6. Chemnitzia Berthaudi, Dumortier, Etudes Pal. sur les Depots 



Jurassiques du Bassin du Rhone, p. 174, tab. xiv, fig. 2, 1867. 



Chemnitzia Tylori, Tate, Quart. Jour, GeoL Soc, Vol. xx, p. 313 (1867), 



Shell turreted, elongated, consisting of ten whorls separated by a deep 

 suture, concave, and ornamented by about twenty very prominent curved 

 smooth ribs; the sulci faintly striated; base slightly carinated, smooth or faintly 

 radiated. Total length "3 inch, breadth of last whorl '07 inch. 



Affinities and Differences. — By its ornamentation closely allied to C. costifera, 

 Piette, and Cerithium Henrici, Martin, but differs from the former apparently 

 in the proportion of its dimensions, and in the less arched outline of the costae ; 

 and from the latter in being only about half the length of that shell, which is pro- 

 vided with only eight whorls. I have no hesitation in referring the shell I had 

 described as C. Tylori to C. Berthaudi, Dumortier, which has priority by some 

 months. 



Geological Position. — C. Berthaudi is a common shell in the zone of "A. 

 angulatus," Island Magee, Co. Antrim. The type of the species is unique, 

 and was obtained from the zone of "A. Bucklandi" at Peronne, Rhone. 



7. Solarium Thomsoni, nov. spec, Plate I. fig. 9, 



Shell orbicular, a little wider than high, spire slightly raised, composed of 

 four whorls, smooth, or ornamented with about 6 raised lines ; last whorl 

 rounded, smooth ; aperture quadrate ; base flat, with fine strice of growth ; 

 umbilicus narrow and slightly crenulated on its border. Height, "075 inch ; 

 diameter, '085 inch. 



Remarks. — S. Thomsoni is allied to S. lenticular e, Terq., but differs in its- 

 more embracing whorls and Rotella-like appearance, in its smaller umbilicus, 

 and its more conical form. 



Geological Position — Zone of " A. angulatus, " Glenarm ; (rare, R. T). 



The species is dedicated to Professor Wyville Thomson, F.R. S., President 

 of the Natural History Society, Belfast. 



8. Crypt/ENIa Brycei. Tate, Quart. Jour. Geol. Soc, Vol. xxiii., p, 



413 (1867). Plate I. fig. 13. 

 Shell subdiscoid, depressed ; test thin, whorls four, nearly flat or slightly 

 concave ; bluntly carinated ; upper surface of the whorls transversely striated ; 

 base convex, smooth ; callosity large, circumscribed by a sulcus, slightly exca- 

 vated near the columella lip ; siphonal band narrow, rather above than below 

 the keel ; aperture, sub-triangular. 



