284 CAMBRIAN BRACHIOPODA. 



395q (references tollow species). (For stratigraphic position and association, see p. 144.) Upper Cambrian: Sand- 

 stone below the Obolus conglomerate at Ontika, about 95 miles (153 km.) east of Eeval and 30 miles (48 km.) 

 west of Narwa, Government of Esthonia, Russia. 



Obolus (Schmidtia) celatus orbiculatus [Mickwitz, 1896, p. 165]. 



Obolus (Schmidtia) celatus prsecisus [Mickwitz, 1896, p. 166]. 



395r (references follow species). (For stratigraphic position and association, see p. 144.) Upper Cambrian: 

 Sandstone below the Obolus conglomerate at Isenhof, 85 miles (137 km.) east of Reval, Government of 

 Esthonia, Russia. 



Obolus (Schmidtia) celatus orbiculatus [Mickwitz, 1896, p. 165]. 



Obolus (Schmidtia) celatus prsecisus [Mickwitz, 1896, p. 166]. 



395s [Mickwitz, 1896, p. 163]. (For stratigraphic position and association, see p. 144.) Upper Cambrian : Schmidtia 

 conglomerate (part of the Obolus conglomerate) at Asserien, 75 miles (121 km.) east of Reval, Government of 

 Esthonia, Russia. 

 Obolus (Schmidtia) celatus. 



395t [Mickwitz, 1896, p. 163]. (For stratigraphic position and association, see p. 144.) Upper Cambrian: Schmidtia 

 conglomerate (part of the Obolus conglomerate) at Ontika, about 95 miles (153 km.) east of Reval and 30 

 miles (48 km.) west of Narwa, Government of Esthonia, Russia. 

 Obolus (Schmidtia) celatus. 



395u [Mickwitz, 1896, p. 163]. (For stratigraphic position and association, see p. 144.) Upper Cambrian: Schmidtia 

 conglomerate (part of the Obolus conglomerate) at Isenhof, 85 miles (137 km.) east of Reval, Government of 

 Esthonia, Russia. 

 Obolus (Schmidtia) celatus. 



395v [Eichwald, 1843, p. 147]. (For stratigraphic position and association, seep. 143.) Passage beds between the 

 Upper Cambrian and the Ordovician: Sandstone on Odensholm Island, about 55 miles (88.6 km.) west of 

 Reval, Government of Esthonia, Russia. 

 Obolus (Mickwitzella) siluricus. 



395w [Eichwald, 1843, p. 147]. (For stratigraphic position and association, see p. 143.) Passage beds between the 

 Upper Cambrian and the Ordovician: In the chlorite-b earing sands in the limestone beds at Pawlowsk, near 

 St. Petersburg, Russia. 



Obolus (Acritis) antiquissimus. 



Obolus (Mickwitzella) siluricus. 



395x [Lamansky, 1901, p. 617]. (For stratigraphic position and association, see p. 143.) Passage beds between the 

 Upper Cambrian and the Ordovician: Glauconitic sandstone (correlated by Lamansky, 1901, p. 617, with 

 the Upper Cambrian Ceratopyge slate) in the vicinity of Baltischport, about 30 miles (48 km.) west of 

 Reval, Government of Esthonia, Russia. 

 Obolus (Mickwitzella) siluricus. 



395y [Kutorga, 1848, p. 281]. (For stratigraphic position and association, see p. 143.) Passage beds between the 

 Upper Cambrian and the Ordovician: Sandstone on Pulkowa Brook, near St. Petersburg, Russia. 

 Obolus (Mickwitzella) silm-icus. 



395z (references follow species). (For stratigraphic position and association, see p. 143.) Upper Cambrian: Obolus 



sandstone at Jamburg on Louga (Luga) River, Government of St. Petersburg, Russia. 

 *Obolus apollinis [Eichwald, 1829, p. 274, and U. S. National Museum]. 

 *Obolus apollinis ingricus [Eichwald, 1829, p. 274]. 

 Obolus apollinis quenstedti [Mickwitz, 1896, p. 144]. 



396 (references follow species). (For stratigraphic position and association, see p. 143.) Passage beds between the 



Upper Cambrian and the Ordovician: "Glauconite sandstone" at Baltischport, 30 miles (48 km.) west of 



Reval, Government of Esthonia, Russia. ' 



Obolus (Mickwitzella) siluricus [Mickwitz, 1896, p. 198, and U. S. National Museum]. 

 Lingulella (Leptembolon) lingulseformis [Mickwitz, 1896, p. 203]. 



396a (references follow species). (For stratigraphic position and association, see p. 143.) Passage beds between the 



Upper Cambrian and the Ordovician: "Glauconite sandstone" at Leppiko, near Leetz, on the eastern side 



of the Baltischport peninsula, about 25 miles (40.3 km.) west of Reval, Government of Esthonia, Russia. 

 *Obolus (Mickwitzella) siluricus [Mickwitz, 1896, p. 198, and U. S. National Museum]. 

 *Lingulella (Leptembolon) lingulaeformis [Mickwitz, 1896, p. 203, and U. S. National Museum]. 

 *Lingulella (Leptembolon) lingulaeformis solidus [Mickwitz, 1896, p. 205]. 



396b (references follow species). (For stratigraphic position and association, see p. 143.) Passage beds between 



the Upper Cambrian and the Ordovician: "Glauconite sandstone" at Fall, 15 miles (24 km.) west of Reval, 



Government of Esthonia, Russia. 

 Obolus (Mickwitzella) siluricus [Mickwitz, 1896, p. 198]. 

 Lingulella (Leptembolon) lingulseformis [Mickwitz, 1896, p. 203]. 



