Hyde. — Camarophorella. 
PLATE 9. 
Camarophorella mutabilis. 
Fig, 44. Specimen showing interior of beaks, the hinge plate, b, with the 
crural bases, from beneath which the median septum is broken 
away, and the tip of the spondyHum, almost all of which is wanting. 
In the spondylium is seen the thickened ring which surrounds 
the pedicle opening and between it and the hinge plate, the inner 
surface of the deltidial plates, a. X S. 
Fig. 45. Anterior view of a jugum of a small specimen; a portion of the left- 
hand primary lamellae has been restored to its point of attach- 
ment to the crus, the present extent being indicated in figure 46. 
The specimen shows well the circular plate, the ventral end (upper 
in figure) of which is molded around the underlying imited lamellae 
of the jugum. X 8. 
Fig. 46. Lateral view of same specimen in which the primary lamellae have 
been partly restored (indicated by lighter color) to show compact 
nature of the entire structure and extent of the primary lamellae. 
X 8. 
Fig. 47. Posterior view of same specimen, the left primary lamellae of 
which is represented as entirely broken away to expose the 
secondary lamella of the jugum. The saddle formed by the united 
branches of the primary lamellae, c, the constriction of the united 
secondary lamellae of the jugum just ventral to (above) the tip 
of the saddle, b, and the under surface of the circular plate, a, 
are shown. X 8. 
Figs. 48, 49. Anterior and lateral views of jugvun of an average-sized speci- 
men. X 4. 
Fig. 50. Specimen of moderate size showing the high median septum of the 
brachial valve, the hinge plate from which the crura have been 
broken and the brachial platform with a slight indication of the 
secondary septum on it. This platform should be represented 
as placed slightly higher on the anterior end of the median sep- 
tum. X 4. 
