384 CAMBKIAN BRACHIOPODA. 



p. 68]) Drift bowlder of Obolus sandstone, Erskolmen Island, parish of Borstil, southeast of Gregrund, Province 

 of Stockholm; and (390m) conglomerate overlying the "glauconite sand" at Horn, Oeland Island; all in Sweden. 



middle Cambrian : (368) Quartzitic sandstone in the Pepper Mountains, near Sandomierz, on the Vistula, Russian 

 Poland. 



Obolus apollinis ingeictjs (Eichwald). 



Obolus ingricus Eichwald, 1829, Zoologia specialis, vol. 1, p. 274. (Described in Latin as a new species.) 



Obolus ingricus Eichwald, 1843, Beitrage zur Kenntniss des russischen Reiches, Bd. 8, No. 2, pp. 140-141. (Char- 

 acterized and discussed in German.) 



Obolus apollinis Eichwald, de Verneuil (in part), 1845, G^ologie de la Russie d'Europe, byMurchison, de Verneuil, 

 and de Keyserling, vol. 2, pt. 3, pp. 290-292 (not PL XIX, figs. 3a-d, which represent specimens of Obolus apol- 

 linis). (Described and discussed in French. The reference includes Obolus (Acritis) antiquissimus, Obolus 

 (Michwitzella) siluricus, Obolus apollinis, and Obolus apollinis ingricus, Obolus apollinis being figured.) 



Obolus ingricus Eichwald, voN Leuchteneerg, 1843, Beschreibung einiger neuen Thierreste der Urwelt von Zarskoe- 

 Selo, p. 16, PL II, figs. 7 and 8. (Not seen.) 



Aulonotreta polita Kutorga (in part), 1848, Verhandl. Russ.-kais. min. Gesell. St. Petersburg for 1847, pp. 279-282 (not 

 PL VII, figs. lOa-f , which represent specimens of Obolus apollinis.) (Described and discussed in German as a 

 new species. The text includes Obolus apollinis ingricus, Obolus (Mickwitzella) siluricus, and Obolus apollinis, 

 the last species being figured.} 



Obolus ingricus Eichwald, 1860, Letheea rossica, ancienne p6riode,vol. 1, sec. 2, pp. 926-927. (Described and discussed 

 in French.) 



Obolus apollinis ingricus (Eichwald), Mickwitz, 1896, M^m. Acad. imp. sci. St.-P6tersbourg, 8th ser., vol. 4, No. 2, 

 pp. 137-140, PL I, figs. 15-28. (Described and discussed in German.) 



Mickwitz states that this shell has the same form as 0. apollinis but that it is much larger 

 and the surface is more frequently and strongly marked by the concentric strias and lines of 

 growth ; the central pit of the ventral valve is more pear-shaped. A full description is given of 

 the details of exterior form and interior markings of the valves so far as known to him. 



Formation and locality." — ^TTpper Cambrian : (336a) Obolus sandstone at Podolova (Putalova?) on Ijora (Ischora) 

 River; and (395z) Obolus sandstone at Jamburg on Louga (Luga) River; both in the Government of St. Petersburg, Russia. 



(395) Obolus sandstone at Joa, near Jegelecht, 12 miles (19.3 km.) east of Reval; (395a) Obolus sandstone at Tihala, 

 near Jegelecht, 12 miles (19.3 km.) east of Reval; (336c) Obolus sandstone at Reval; (336t) Obolus sandstone at Wiems, 

 5 miles (8 km.) north -northeast of Reval; and (338s) Obolus sandstone at Narwa; all in the Government of Esthonia, 

 Russia. 



Obolus apollinis maximus Mickwitz. 



Plate VII, figure 9; Plate XIV, figures 7, 7a. 



Obolus apollinis maoyimus Mickwitz, 1896, M6m. Acad. imp. sci. St.-P^tersbourg, 8th ser., vol. 4, No. 2, pp. 140-143, 

 PL I, figs. 29-38. (Described and discussed in German as a new variety.) 



Mickwitz states that this shell is very large, 21 mm. or more in diameter. It has more 

 regular, radial, and concentric striations than the variety ingricus and the surface is smoother. 

 The ventral valve near the beak is very thick. An elaborate description is given, accompanied 

 by full illustration. 



Formation and LOCALirT.^trpper Cambrian: (395) Obolus sandstone at Joa, near Jegelecht, It miles {19.3 km.) 

 east of Reval; and (395! [Mickwitz, 1896, p. 142]) Obolus conglomerate throughout the east Baltic region; both in the 

 Government of Esthonia, Russia. 



(338j) Obolus sandstone at Staroja Ladoga, Government of Novgorod, Russia. 



Obolus apollinis quenstedti (Mickwitz). 



Text figures 34A-B, page 374. 



Ungula convexa Pander, 1830, Beitrage zur Geognosie des russischen Reiches, pp. 59 and 163, PL XXVIII, figs. la-b. 



(Characterized in German on p. 59; description of plate on p. 163.) 

 Ungula transversa Pander (in part), 1830, idem, pp. 59 and 154, PI. Ill, fig. 24 (not PL XXVIII, fi^s. 7a-b and 



(?) 8a-b, which represent specimens of Obolus apollinis). (Characterized in German on p. 59; description of 

 , plate on p. 154.) 



a All of the localities mentioned are taken from the references given in the synonymy. The authority for each locality cited will be fomid 

 in the list of localities, pp. 161-291. 



