Contributions to Invertebrate Palaeontology. 615 



Grammtsia bisulcata Conrad. Page 559. 

 Fig. 19. A right valve, natural size. 



AcTiNODESMA suBREOTA Wliitf. Page 557. 

 Fig. 20. Impression in the stone of a left valve. 



PLATE XII. . 



LiNGULA LiGEA Hall. Page 573. 



Fig. 1. View of a specimen from the Huron Shales at Delaware, Ohio. 

 Fig. 2. The same enlarged, to show muscular imprints. 



Orthis TIOGA Hall. Page 561. 

 Fig. 3. View of a concretion containing valves of two individuals, natural size. 



Pal^aneilo similis Whitf. Page 561. 

 Fig. 4. Side view of the specimen described, natural size. 

 Fig. 5. Cardinal view enlarged showing impressions of teeth. 



Plumulites Newberryi Whitf. Page 573. 



Fig. 6. A small plate of the prevailing form. 



Fig. 7. An elongated plate probably from near the extremity of the body. 



Figs. 8-10. Three plates, showing as many forms. 



Fi^ 11. View of a conical plate which overlies a second, from a concretion. 



EcHixocARis suBLEVis Whitf. Page 565. 



Fig. 12. View of one side of a concretion showing a part of a valve and the 

 abdomen and telson of this species, natural size. 



Fig. 13. View of the left side of a carapace as taken from the other half of 

 tlie same concretion as Fig. 12, enlarged. 



Fig. 14. The abdomen and telson enlarged from the specimen Fig. 12. 



EcHiNOCARis PUSTULOSA Whitf. Page 567. 

 Fig. 15. The right valve of a carapace enlarged. 



EcHiNocARis MULTiNODOSA Wliitf. Page 568. 

 Fig. 16. Dorsal view of both valves of a carapace, natural size. 



Aristozoe Canadensis Whitf. Page 572. 

 Fig. 17. Dorsal view of the specimen described, natural size. 

 Fig. 18. Lateral view of the same showing the three rows of small pustules 

 near the basal margin. 



