PLATE LII—Continued. 
Anoplotheca venusta, Schiiiu’. 
Fig. 20. The inteiior of a brachial valve, enlarged; showing the cardinal process and muscular impres¬ 
sion. 
Fig. 21. An internal cast of the pedicle-valve, enlarged; showing the diductor scars and vascular 
impressions. 
Figs. 22, 23. Ventral and dorsal views of the exterior. 
Fig. 24. An enlaj'ged view of a specimen showing, by the removal of a portion of the pedicle-valve, the 
spiral cones, their form and direction. 
(Figs. 20, 21, 24 are after Sandbeeger; figs. 22, 23 after Schnur.) 
Middle Devonian. Eifel, Germany. 
Genus UNCITES, Defrance. 
Page 113. 
Uncites gryphus, Schlotheim. 
Fig. 25. A specimen from which a portion of the pedicle-valve has been broken, exposing the interior and 
showing the lateral pouch-shaiied expansions of both valves and the incurved beak and crura 
of the brachial valve. (Davidson.) 
Middle Devonian. Chimay, Belgium. 
Fig. 26. A profile of a specimen retaining both valves; showing their convexity, and the prolongation of 
the beak of the pedicle-valve. (Davidson.) 
Middle Devonian. Bajfrath, Germany. 
Fig. 27. A dorsal view of a medium-sized specimen ; showing the character of the exterior and the deep 
delthyrium. (Davidson.) 
Middle Devonian. Chimay, Belgium. 
Fig. 28. A dorsal view of a large individual with distorted unciform beak. (F. Roemer.) 
Middle Devonian. Eifel, Germany. 
Fig. 29. The inferior of the umbonal region of the brachial valve, enlarged; showing the hinge-plate, 
lateral pouches, and grooved ridges extending forward from the base of the hinge-plate. 
(Davidson.) 
Middle Devonian. Torquay, England. 
Genus KARPINSKIA, Tschernyschew. 
Page 176. 
Karpinskia conjugula, Tschernyschew. 
Figs. 30-32. Profile, dorsal and ventral views of the exterior of conjoined valves. 
Fig. 33. A transverse section ; showing the form of the spii'al cones and their convergence into the cavity 
of the bi'achial valve. 
(Tschernyschew.) 
Lower Devonian. Ural Mountains, Russia. 
Subgenus GRUENEWALDTIA. Tschernyschew. 
Page 175. 
Gruenewaldtia latilinguis, Schnur. 
Figs. 34-36. Dorsal, profile and frontal views; showing the contour and exterior markings of the species. 
(SCIINUR.) 
Middle Devonian. Gerolstein, Germany. 
