PLATE VIII. 1 



Orthoceras Sollasi, A. H. Foord. 



Fig. 1 a. Specimen showing the body-chamber and the greater part of the 

 septate portion of the shell. (Note the crescentic depression at the anterior end of 

 the body-chamber just below the margin of the aperture.) 1 b. Transverse section 

 with siphuncle. 1 c. Portion of the test showing the striae, natural size. 1 d. 

 Figure of the stria? (somewhat diagrammatic), enlarged to show bifurcations. 1 e. 

 Another specimen, somewhat more complete than 1 a, showing the septa where 

 the test is removed ; the slight constriction near the aperture is well seen. 1 /. 

 Longitudinal section showing septation and a fragment of the siphnncle. Clane. 

 Dublin Museum of Science and Art. (Page 23.) 



Orthoceras multistriatum, A. H. Foord. 



Fig. 2 a. Fragment with body-chamber and a good deal of the septate part of 

 the shell. 2 b. Longitudinal section showing the septa and siphuncle. Little 

 Island. Dublin Museum of Science and Art. (Page 24.) 



Okthoceras perellipticum, A. H. Foord. 



Fig. 3f/. Fragment of the septate part of a specimen. 3 b. Transverse section 

 showing siphuncle. 3 c. Imbricating strias greatly enlarged. Little Island. 

 Museum of Queen's College, Cork. (Page 25.) 



Okthoceras perconicum, A. H. Foord. 



Fig. 4 a. Fragment showing the greater part of the body-chamber and some 

 of the septa. 4 b. Transverse section, the siphuncle not preserved. Clane. 

 Dublin Museum of Science and Art. (Page 27.) 



1 All the figures in this and the following Plates represent the specimens of the natural size unless 

 the contrary is stated. 



