Hyde. — Camarophorella. 
PLATE 7. 
Camarophorella mutabilis. 
Fig. 13. Brachidium from the posterior end of the shell, showing the jugum 
resting on the median septum of the brachial valve and the 
brachial platform in transverse section. The primary lamellae, 
seen on either side of the median septum, are not continued to 
their point of attachment to the crura. Semidiagrammatic 
from the same individual from which figures 37 and 38 (pi. 8), 
were drawn. X about 4. 
Fig. 14. Longitudinal section showing relation of platforms and musculature 
to jugum. The outline of the shell, spondylium, adductor muscle 
scar in spondylium, hinge plate, and crus are drawn from a single 
specimen. X 5. 
Figs. 15, 16. Outlines of spondylium based largely on the one illustrated in 
figures 42 and 43 (pi. 8), showing muscle scars as far as known. 
The outline of the median tongue-shaped adductor muscle is 
always readily discernible. An indistinct subelliptical impres- 
sion near the base of the crura is interpreted as the point of 
attachment of one of the pedicle muscles. 
Fig. 17. Outline of brachial platform and hinge plate showing area of im- 
pression of adductor muscles. 
