PLATE IV. 



Pleurotomaria Valeria, Billings (page 23). 



Figure 1. Basal view of the type of the species. 



" la. Specimen from Durham, showing spire and test, which the type 

 does not. 



Pleurotomaria Durhamensis (page 24). 

 Figure 2. An unusually perfect cast of the interior of the shell. 



MuRCHisoNiA Hespelerensis (page 24). 

 Figure 2. Lateral view of a cast. 



Mtjrchisonia constricta (page 25). 

 Figure 4. Specimen with the test preserved. 



MuRCHisoNiA TURRiTiFORMis, Hall. Y&w (page 26). 

 Figure 5. The most perfect specimen in the Survey collection. 



MURCHISONIA CoNRADi, Hall (page 27). 

 Figure 6. A stout form of this species, from Flora. 



MURCHISONIA MACROSPIRA, Hall (jKlge 27). 



Figure 7. Drawing of gutta-percha impression from a mould of the interior 

 collected at Gait. 

 " la. Small specimen from Flora, with the whole of the test preserved. 



MURCHISONIA SOLUTA (page 28). 



Figure 8. Cast of the interior of the shell of this species, with the apical 

 portion broken off. 

 " 8a. Cast of the earlier whorls of the shell. 



MURCHISONIA. Sp. Undt. (page 29). 



Figure 9. Fragment of cast of a shell with characters intermediate between 

 M. macrospira and if. soMa, 



