Pa A, Sob: 
GLYPTASPIS VERRUCOSUS, Newb. (p. 158). 
Fig. 1. Ventromedian plate, one-half natural size. 
2. Lateral plate from dorsal ? surface, natural size. 
MYLOSTOMA VARIABILIS, Newb. (p. 165). 
3,4. Upper palate teeth, natural size. 
5. Crown of peculiar inferior conical tooth, natural size. 
All from Cleveland shale, Sheffield, Ohio. 
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