PLATE LXII—Continued. 
Subgenus CAMAKOPHORELLA, s.-gen. nov. 
Page 215. 
Camarophorella lenticularis, White ;uid Whitfield. 
Fig. 46 An internal cast of the pedicle-valve ; showing the cavity left by the spondyliuni and median seij- 
tum. The external surface of the shell is smooth, the low. radiating ridges shown in this figure 
and in fig. 47, being impressions of internal sinuses, probably vascular in their nature. X 2. 
Fig. 47. An internal cast of the lirachial valve ; showing the imx>ressions of sx>ondylium and median seji- 
tum. In this valve the spondylium is flat and the suxiporting sex)tum x^enetrates it, extending 
for a short distance into the interior cavity of the shell. X 2. 
Fig. 48. A cardinal view of an internal cast of the xiedicle-valve ; showing the filling of the siiondylium and 
the cavities left by the median sexituin and the oblique dental x>lates. X 2. 
Yellow sandstones of the Burlington group. Burlington,, Iowa. 
Genus LYCOPHORIA, Lahusen. 1885. 
Page 230. 
Lycophoria nucella, Dtdmaii. 
Figs. 49, 50. Dorsal and profile views of a finely xilicated, orbicular specimen. In fig. 49, the muscular area 
is faintly outlined through the substance of the brachial valve. 
Fig. 51. The exterior of the brachial valve of a more S'rongly xdicated 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 two valves; showing the thickening of the umbonal region 
of the brachial valve and the projection of the cardinal 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 xjlates and erect, bifurcate cardinal x)rocess. X 2. 
Lower Silui-ian. Near St. Petei'shurg, Russia. 
