PLATE XXV. 



Fig. ]. — Difln/rocaris glabra, V^f. & E. Part of the dorsal ridge of one of 

 two valves. X 2^. B. M., 59541, No. 6. (Page 139.) 



Fig. 2.—D. glabra, W. & E. Part of the dorsal ridge of the left valve. X 21. 

 B. M., 59541, No. 8. (Page 139.) 



Fig. 3 a. — D. instgnis, sp. uov. Part of right valve among displaced fragments 

 of tvro valves. Mus. Leeds Coll. x 2^. (Page 159.) 



Fig. 3 b. — The same. Part of the surface. X 10. 



Fig. 3 r. — The same. Part of the surface. X 50. 



Fig. 4rt. — Possibly from the same specimen. Part of a dorsal ridge. X 3. 



Fig. 4 b. — The same. Part of its surface. X 10. 



Fig. 4o. — The same. Outline of its elevation. X 10. 



Fig. 4f7. — The same. Part of its surface. X 10. 



Fig. 4 e. — The same. Part of its surface. X 50. 



Fig. 5 ffl. — Probably from the same specimen. Fragment of a valve. X 10. 



Fig. 5 b. — The same. Part of its surface. X 50. 



Fig. 6 a.— D. Sconleri, M'Coy. Carapace and tail. Copied from M'Coy's 

 ' Carb. Foss. L-eland,' pi. xxiii, fig. 2. (Page 155.) 



Fig. 6 b. — The same. -) 



u- /:; m \ Parts of the ridges, 



rig. DC. — riie same. ) = 



Fig. 7.—D. sp. (?). From a plaster cast. Griffith Coll. Dublin. (Page 157.) 



Fig. 8 a. — Hlhbertia orbicularis, gen. and sp. nov. X 2. (Burdiehouse.) 



Fig. 8 h. — The left-hand postero-ventral angle. X 5. 



Fig. 9 a.—D. Golei {?) vel tricornis {F). A separate dorsal ridge. M. G. S. Sc, 

 F ^,No. 20. (Page 175.) 



Fig. 9 b. — The same. Part of its surface. X 5. 



Fig. 9 G. — The same. Outline of its elevation. X 5. 



Fig. 10 a. — Kirkbya plicata, J. & K. Carapace, showing the right valve. X 25. 

 On the same specimen with fig. 9. (Page 175.) 



Fig. IOZj.— The same. Dorsal view. X 25. 



Fig. 10 c. — The same. Part of the surface. X 50. 



