PLATE LXII— Continued. 



Subgenus CAMAROPHORELLA, s.-gen. nov. 



Page 215. 



Camarophorella lenticularis, White iiiid Whitfield. 



Fig. 46 An internal cast of the pedicle-valve ; .showing- the cavity left by the sijondylium anil median sep- 

 tum. The external surface of the shell is smooth, the low. i-adiating ridges shown in this figui-e 

 and in fig. 47, being impressions of internal sinuses, probably vascular in their nature. X 2. 



Fig. 47. An internal cast of the brachial valve ; showing the impressions of spondylium and median sep- 

 tum. In this valve the spondylium is flat and the sujiporting septum penetrates it, extending 

 for a short distance into the intei'ior cavity of the shell. X 2. 



Fig. 48. A cardinal view of an internal cast of the pedicle-valve ; showing the tilling of the spondylium and 

 the cavities left by the median septum and the oblique dental plates. X 2. 

 Yellow sandstones of the Burlington gi-olip. Burlington, Imea. 



Genus LYCOPHORIA, Lahusen. 1885. 



Page 230. 



Lycophoria nucella, Dahuan. 



Figs. 49, 50. Dorsal and profile views of a finely plicated, orbicular specimen. In fig. 49, the muscular area 



is faintly outlined through the substance of the brachial valve. 

 Fig. 61. The exterior of the brachial valve of a more s'rongly plicated shell which has been somewhat worn 



in the umbonal region, disclosing the outline of the elongate muscular area. 

 Fig. 52. A longitudinal median section of the iwo valves; showing the thickening of the umbonal region 



of the brachial valve and the projection of tlie caixiinal process into the umbonal cavity of the 



pedicle-valve. 

 Fig. 53. Cardinal view of specimen transversely sectioned in the umbonal region, the pedicle-valve being 



above ; showing the dental plates and erect, bifurcate cardinal process. X 2. 

 Lower Silui-ian. Near St. Petersburg, Russia. 



