INDEX 4/1 



PAGE 



Obolits fiieinbranaceous, new species 6i, pi. 7, fig. Ii 



compared with Obolus feistiiiantcli 61 



stratigraphic position and association 209 



Obolus minimus, compared with Obolus parvus 61-62 



Obolus parvus, new species 6r, pi. 7, figs. 10 and 100 



associated fossils listed 6r 



compared with LinguleUa (Lingulepis) longincrvis 61 



Obolus niiiiiimis 61-62 



mentioned 22 



stratigraphic position and association 214 



Obolus rotundatus, stratigraphic position and association 176, 179, 180 



Obolus siluncus Eichwald, mentioned 70 



Obolus smithi, new species 62, pi. 7, fig. ga^ 



associated fossils listed 62, 100 



compared with Obolus lauiborni 63 



Obolus zuillisi 63 



mentioned 60, 100 



Obolus tetonensis, compared with Obolus tetoncusis Icda 63 



compared with Obolus zvortheni 64 



Obolus tetonensis leda, new variety, characterized, not figured 63 



stratigraphic position and association 175 



Obolus willisi, compared with Obolus smithi 63 



Obolus zvortheni, new species 63, pi. 7, fig. 17 



compared with Obolus discoideus 64 



Obolus tetonensis 64 



Obolus ( Westonia) escasoni 64 



Obolus sp. undt., stratigraphic position and association. .192, 193, 196, 201, 208 



Obolus (Acritis), classification of 142, 144 



Obolus (Broggeria), classification of 142, 144 



Obolus (Broggeria) salteri, associated fossils listed 85 



mentioned 85 



Obolus (Fordinia), new subgenus, characterized and discussed 64 



cardinal area in species of, discussed 67 



classification of 142, 144 



compared with Elkania and Obolus 65 



evolution of pi. 11 (pp. 140-141 ) 



platform of 159 



Obolus (Fordinia) bclhtlus, compared with Obolus (Fordinia) perfectiis. 



64, 66, 67 



stratigraphic position and association 193 



Obolus (Fordinia) gilberti, new species 65, pi. 7, figs. 15 and 15a 



compared with Dicellomus politus 65 



Obolus (Fordinia') bellulus 65 



Obolus (Fordi)iia) perfectus 65, 66 



stratigraphic position and association 179 



^Figure 9 represents a specimen of Micromitra (Paterina) major, which 

 was included by mistake. 



