PLATE 83. 
Fig. 1. 708. 19. Murchisonia bivittata. (Pag. 345.) 
1 a. A cast of six volutions from the central part of the shell. 
1 6. A longitudinal section of several volutions, showing the columella, marked by a double spiral fold, and 
the edges of the broken shell. 
Fig. 2. 709. 20. Murchisonia longispika. (Pag. 345.) 
2 a. A mould of the middle part of the spire, preserving a portion of the shell and columella near the base. 
2 b. A fragment showing in the upper part the cast of the interior; the lower part of the specimen preserves 
the shell, which is divided longitudinally. 
Fig. 3. 710. 21. Murchisonia boydii. (Pag. 346.) 
Fig. 4. 711. 22. Murchisonia loganii. ( Pag. 346.) 
4. a. A specimen, the upper part of which is a mould of the shell, while the lower part preserves the cast of 
the interior with some portions of the shell and columella. 
4 6. A cast preserving several volutions below the apex. 
Fig. 5. 712. 23. Murchisonia macrospika. (Pag. 346.) 
Fig. 6. 713. 24. Murchisonia turritiformis. (Pag- 347.) 
6 a. The cast of two volutions, near the base of the shell. 
6 b. A cast of five volutions, imperfect at both extremities. 
Fig. 7. 714. 2. Subulites ventricosa. ( Pag. 347.) 
7 a. A small specimen having much of the last volution broken off, but preserving the spire complete. 
7 b. A large individual with the spire incomplete, but preserving the last volution entire. 
Fig. 8. 722. 7. Calymene-. (Pag. 350.) 
