116 NEW YORK STATE MUSEUM 



PLATE 7 



Chonetes hudsonica sp. nov. 



Page 49 

 Flo. 



1 The exterior of the pedicle-valve 



2 The interior of the brachial valve 



3 An external cast of the pedicle-valve 

 4, 5 Pedicle and brachial valves. x2 



6 The surface striations enlarged. x4 



Chonostrophia complanata Hall 



Page 50 



7 Ventral view of a small specimen 



8 Internal cast of a pedicle-valve of average size 



9 The interior of the pedicle-valve 



10 Internal cast of a pedicle-valve with somewhat more 



elongate outline 



11 Exterior of a pedicle- valve of a large individual 



12 Enlargement of the surface, xo 



13 Interior of a large pedicle-valve 



Anoplia nudeata Hall 



Page 51 



14 Dorsal view of a specimen retaining both valves. x3 



Orthothetes becraftensis sp. nov. 



Page 51 



15 The interior of a pedicle- valve 

 16, 17 Exteriors of pedicle- valves 



18 The cardinal process of the brachial valve. x3 



19 The exterior of a small brachial valve. x2 



20 Exterior of a small pedicle-valve 



21 The interior of a young pedicle-valve attached by the 



substance of its shell to the surface of a M e r i 

 stella. x2 



