PLATE XV. 



Poterioceras fusiforme, J. de G. Sowerby, sp. 



Fig. 1 a. Imperfect specimen showing the septation on the ventral side, and 

 the greater part of the body-chamber. 1 b. A septum of the same, showing the 

 position of the siphuncle. 1 c. The same specimen viewed laterally, exhibiting 

 the flattened ventral and inflated dorsal profiles. 2 a. Ventral view of another 

 specimen, nearly perfect, the septate part almost covered by the test. The base 

 of the body-chamber is seen along the line a, b, in 2 b, which is a lateral view of 

 the same specimen. 2 c. A septum of the same, showing the siphuncle. The 

 dotted line added to fig. 2 c enables it to be more readily compared with 2 b, 

 which is placed for that purpose in the same position. 3. Posterior end of 

 Sowerby's type specimen, contained in the British Museum. St. Doulagh's. 

 Dublin Museum of Science and Art. (Page 43.) 



