PLATE XXVII. 

 DisciTOCERAS Leveilleanum, L. 0. de Eonincl; sp. 



Fig. 1 a. Lateral view of a young and perfect individual, somewhat distorted ; 

 the margin of the aperture is seen, and the lines of growth near it are very 

 distinct. (The light spots near the margin of the whorl, above the break in the 

 shell, are of no significance.) 1 b. Front view of the same specimen. Clane. 

 Dublin Museum of Science and Art. (Page 102.) 



Fig. 2 a. Lateral view of a remarkably fine and pei'fect individual, slightly 

 distorted; the figure shows well the fine and regular lines of growth, and the fine 

 longitudinal ridges extending to the beginning of the last whorl. 2 h. Peripheral 

 view of the same specimen, showing the deep sinus in the margin of the aperture. 

 2 c. Ornamentation of the penultimate whorl enlarged. Clane. Dublin Museum 

 of Science and Art. (Page 102.) 



Fig. 3. Lateral view of an uudistorted specimen, showing part of the septation 

 and the whole of the body-chamber. Ballyhomon. Dublin Museum of Science 

 and Art (Geological Survey Collection). (Page 102.) 



? DisciTOCERAS DISCORS, F. M'GoiJ, Sp. 



Fig. 4 a. Lateral view of a specimen wanting a considerable part of the body- 

 chamber; its base is where the fracture is shown, ^h. Front view of the same. 

 4 c. Part of the last whorl of the same specimen extending to the base of the 

 body-chamber, showing the zone of impression and the position of the siphuncle. 

 (These figures ai*e reduced to about two-thirds of the natural size.) 4d. View 

 of a septum (natural size), showing the position of the siphuncle and the annular 

 lobe. 4 e. Profile view of the same. Ballygarrane. Dublin Museum of Science 

 and Art. (Page 104.) 



