PLATE XXIX— Continued. 

 ECHINOCARIS SUBLjEVIS. 

 Page 176. 

 Fig. 11. The type specimen ; drawn from a, gutta-percha impression of the internal surface of the left valve, 

 the posterior portion being slightly restored ; showing the number and arrangement of the 

 nodes, the character of the carina and of the surface ornamentation. 

 Pig. 12. The same, enlarged to two diameters. 



Erie shales. (Portage group.) Paine's Creek, Lake county, Ohio. 

 Pig. 13. A portion of the abdomen and post-abdomen belonging to the carapace ; showing the relatively 

 short somites, their conspicuous lateral and faint dorsal spines, the elevated caudal plate and 

 comparatively short caudal spines. Enlarged to two diameters. 



Erie shales. (Portage group.) Paine's Creek, Lake county, Ohio. 



ECHINOCARIS CONDYLEPIS. 



Page 173. 

 Fig. 14. The expanded valves of the carapace, natural size. 



Fig. 15. The same, enlarged to three diameters, showing the outline of the valves, the number and disposi- 

 tion of the nodes upon the surface, and the character of the lateral carinae. 

 Chemung group. Belmont, Alleghany county. 

 Fig. 16. A left valve somewhat compressed at right angles to the axial line and having the anterior extremity 



slightly broken. 

 Fig. 17. The same, enlarged to four diameters, showing the nodes to be somewhat elongated on account 

 of distortion. 



Chemung group. Belmont, Alleghany comity. 



ECHINOCARIS MULTINODOSA. 



Page 180. 

 Fig. 18. The type specimen of the species, showing the features of the dorsal surface of the carapace. 

 The lateral carina, which appears to be of similar character to that in E. sublwvis, is not well 

 preserved, as the specimen has suffered some distortion about the ventral margins. 

 Erie shales. (Portage group.) Paine's Creek, Lake county, Ohio. 

 Fig. 19. An imperfect specimen, showing with great distinctness the character of the nodes and ornamenta- 

 tion about the hinge. 



Erie shales. (Portage group. ) Paine's Creek, Lake, county, Ohio. 



ECHINOCARIS WHITFIELDI. 

 Page 172. 

 Fig. '20. The left valve of the carapace, showing the outline and proportions, the low, indistinct nodes upon 

 the surface and the short antero-lateral carina. The fine scaly surface markings about the 

 cephalic nodes is not shown. 

 This is the type specimen and is enlarged to two diameters. 

 Portage group. Naples, Ontario county. 

 Fig. 21. An imperfect specimen, natural size, retaining the caudal plate and two of the caudal spines ; 

 showing the strongly tuberculose surface. 



Portage group. Naples, Ontario county. 



