PLATE 25. 
Legend: A. Delthyrium. b. Dental sockets. 
t. Teeth. c. Crural bases. 
d. Dental plates. a. Adductor scars. 
D. Deltaria. r. Diductor scars. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
PC nt a 
Me 
oO 
j. Cardinal process. 
SPIRIFER, Sowzrsy. 
(Frocerratt). 
Page 755. 
SPIRIFER cCRISPUS, Hisinger. 
. Dorsal view of an entire individual. x 2. 
An enlargement of the cardinal portion of the brachial valve. 
. The interior of a pedicle-valve. 2. 
An enlargement of the external surface showing concentric rows of 
spine bases. 
Niagara shales. Western New York. 
SprrifER VanNuUxeEmMtI, Hall. 
. Dorsal view of an entire individual; showing the external characters. 
x 3. 
Lower Helderberg group. Litchfield, N. Y. 
SpPrRIFER CYCLoPTERuS, Hall. 
. Dorsal view of an average example. 
Lower Helderberg group. Schoharie, N. Y. 
SPIRIFER DUODENARIUS, Hall. 
Dorsal view of a normal adult. 
Corniferous limestone. Western New York. 
SPIRIFER L#vIS, Hall. 
. The exterior of a pedicle-valve, bearing faint lateral plications. 
9. An internal cast ofa pedicle-valve ; showing the filling of the muscular 
impression and the ovarian markings. 
Portage group. Ithaca, N. Y. 
202 
