I'LATl*: XI IJ—Contiiiucil. 
Fig. 19. A pygidium showing the lower surface, the extent of the doublure and the i)oiuts of attachment 
of the pygidial appendages. 
Corniferous limestone. Canandaigua, Ontario county. 
Fig. 20. A pygidium with comparatively short spines for this species. 
Corniferous limestone. Locality ? 
Fig. 21. The axis of a pygidium, drawn from an internal cast, showing the median depression and obso¬ 
lescence of the annulations near the extremity. 
Corniferous limestone. Schoharie county. 
Dalmanites (Odontocephalus) bifidus. 
Page 53. 
Fig. 22. A small, imperfect pygidium, showing the extended, exjilanate posterior exti’emity and the stout 
terminal spines. 
Corniferous limestone. Columbus, Ohio. 
Fig. 23. Another pygidium of a young individual. 
Corniferous limestone. Lime Rock, near LeRoy, Genesee county. 
Fig. 24. A large pygidium, showing the normal features of this part. The crust on the original is pai-tly 
broken away, but it has been i-estored in the drawing. 
Fig. 25. The same, drawn in profile. 
Corniferous limestone. Lime Rock, near LeRoy, Genesee county. 
