PLATE X. 

 (All the figures are of the natural size except fig. 7 b and fig, 12.) 



Figs. 1 a, 1 b. — Geratiocaris truncata, H. Woodward. Left valve : 1 a, the 



internal cast ; and 1 b, the hollow impression ; counterparts. British Mus. 



(Page 51.) 



Fig. 2. — G. inornata, M'Coy. Right valve. British Mus. (Page 48.) 



Fig. 3. — The same. Right valve. The specimen figured in the ' Brit. Pal. 



Foss.,' 1851, fig. 4. Cambridge Mus. (Page 49.) 



Fig. 4. — G. Oretonensis, H. Woodward. Left valve. British Mus. (Page 50.) 



Fig. 5. — G. inornata, M'Coy Right valve. Bintish Mus. (Page 48.) 



Fig 6. — G. Buthveniana, T. R. J. & H. W. Right valve, imperfect. British 



Mus. (Page 49.) 



Figs. 7 (I, b. — -C. stygia, Salter var. 7 a, right valve ; 7 b, portion enlarged 



(2 diam.) to show the longitudinal striation on the upper and lower regions of the 



valve. Cambridge Mus. (Page 41.) 



Fig. 8. — (J. leptodacti/lus (?), M'Coy. Portion of the abdomen, probably part of 



the penultimate and ultimate segments. British Mus. (.Page 16.) 



Fig. 9.—G. angusta, T. R. J. & H. W. Style and stylet. British Mus. 



(Page 47.) 



Fig. 10. — G. robusta, Salter. Trifid appendage. Mus. Pract. Geol. (Page 44.) 

 Fig. 11.— C. m,muta, T. R. J. & H. W. Trifid appendage. Owens College 



Mus. (Page 47.) 



Fig. 12. — G. laxn, T. R. J. & H. W. Portion of the Hnear ornament, mag- 

 nified 25 diam. (see PI. VIII, fig. 12). British Mus. (Page 57.) 



