PLATE 39 



Phacops cristata Hall 

 Page 163. 

 Fig. 1. An imperfect cephalon. 



(Grand Tower formation.) (W. M. 23909.) 

 Fig. 2. Pygidium and some pleural segments. (After Hall.) 



Onychodus sigmoides Newberry 

 Page 164. 



Fig. 3. A fragmentary specimen, slightly retouched. 



(Grand Tower limestone.) (W. M. 23912.) 



Proetus crassimarginatuS Hall and Clarke 

 Page 161. 

 Fig. 4. An ordinary pygidium. 



(Grand Tower limestone.) (W. M. 23905.) 



Phacops rana (Green) 

 Page 163. 

 Fig. 5. Figure after Hall. 



Tentaculites sp. undet. 

 Page 157. 

 Fig. 6. A cast of an impression. (X6.) 



(Beauvais sandstone.) (W. M. 23992.) 



Diaphorostoma genevievensis Branson and Williams. 

 Page 156. 

 Figs. 7 and 8. Side and top views of one of the cotypes. 

 Fig. 9. The same specimen as in fig. 8. (X5). 



(Grand Tower limestone.) (W. M. 23893.) 



Cryphaeus boothi Green 

 Page 162. 

 Fig. 10. The best pygidium in the collections. 



(St. Laurent limestone.) (W. M. 23967.) 



Platyceras nodosum Conrad 

 Page 156. 

 Fig. 11. The only specimen in the collections. 



(Grand Tower limestone.) (University of Missouri collection.) 



Proetus haldemani Hall 

 Page 161. 

 Fig. 12. One of the most complete cephala in the collections. 

 (Grand Tower limestone.) (W. M. 23908.) 



