PLATE XVIII. 



Fig. 1 a. — Dithyrocaris glabra, H. Woodward and R. Etheridge, jun. Left 

 moiety or valve. Mus. Geol. Survey Scotland, 4368, F ff, No. 11 (= £ Geol. 

 Mag.,' 1874, pi. v, fig. 4). (Page 136.) 



Fig. 1 b. — The same. Part of the surface, with and without the outermost 

 film. X 40. 



Fig. 2.—D. glabra, W. & E. Right valve. M. G. S. Sc, 4078, F ff, No. 12 

 (=« Geol. Mag.,' 1874, pi. v, fig. 5). (Page 137.) 



Fig. 3 a. — D. ovalis, W. & E. Carapace, crushed and open. M. G. S. Sc, 

 F ^, No. 4 (=« Geol. Mag.,' 1874, pi. v, fig. 1). (Page 140.) 



Fig. 3 b. — The same. Part of the surface. X 40. 



Fig. 4.— D. granulata, W. & E. Left valve. M. G. S. Sc, F \\ No. 6; 

 also PL XX, fig. 2, magnified (= ' Geol. Mag.,' 1874, pi. v, fig. 2). (Page 142.) 



Fig. 5 a.— D. granulata, W. & E. Left valve. M. G. S. Sc, 4076, F ff , 

 No. 13 (=' Geol.' Mag.,' 1874, pi. v, fig. 3). (Page 144.) 



Fig. 5/;. — The same. Antero-dorsal region. X 3^. 



Fig. 6. — D. granulata. W. & E. Carapace. Brit. Mus., 59541, No. 9 ; also 

 PL XX, fig. 1, magnified. (Page 144.) 



Fig. 7.—Calyptocaris striata, Woodward, sp. M. G. S. Sc, M 576 a, F $f , 

 No. 15 (= ' Geol. Mag.,' 1874, pi. v, fig. 6). Two valves pressed together, 

 showing the left imperfect. 



Fig. 8 a. — Dithyrocaris Belli, Woodward. Two valves overlapping, imperfect. 

 B. M., No. 25 (= ' Geol. Mag.,' 1871, pi. iii, fig. 5). (Page 176.) 



Fig. 8 b. — The same. Postero-ventral region of the left valve. X 5. 



Fig. 8 c. — The same. Part of surface. X 15. 



