IPAS By Ee. 
Page. 
SPIRIFERA PINONENSIS...--- ---- ---- 2020 once en ee cece cans nee cn ee ne wan cee nn ee cree coee noes 138 
Figs. 1,1a,b. The original figures of S. argentarius Meek. 
lc,e,f. The original figures of S. Pinonensis Meek. 
1d. Dorsal view of a specimen from the Eureka District, in which the radiating pli- 
cations are finer than in fig. le. Natural size. 
SPIRIFERA RARICOSTA ..---- ------ 022-00 oo ane ce nnn oe wen sen cn cee nnn nae ae semen es esese secs 135 
Fig. 2. Ventral valve of a specimen with numerous plications. 
2a. Same view of a shell with few plications. See plate xiv, fig. 12. 
TREMATOSPIRA INFREQUENS .... .- ---- 2222-222 eee cee enn ens emcees cence cow n ns wane cen ene 151 
Figs. 3,3a,b. Dorsal, ventral, and side views of the type specimen. Natural size. 
CRYPTONEEDAG PINONENSIS)=2 5 22> on eo seee tee e noe eee eee eee eee ee eae 163 
Fig. 4,4 a,b. Dorsal, ventral, and side views of the type specimen. Natural size. 
MYTIEARGA DUBIA -2.25-.-2-6 «22 25- -n 05 oenle witwinin ele nie eee sienna s amisie sional am eae ninmae 168 
Fig. 5. Cast of right valve. Natural size. 
5a. View of anterior side. i 
POSIDONOMYA LEVIS ...- .----- -<20 occ c een e ane cece oe cen enn ee nnn ene tan cone ewe ce wanes 178 
Fig. 6. Right valve. Natural size. 
POSIDONOMYA DEVONICA ..---. --2200 c20- coe ene wenn oe nn ones conn nnn nee nee ene ene en nns 179 
Fig. 7. Right valve enlarged to two diameters. 
MODIOMORPHA OBTUSA .... ---- ---- so secs cons cece cones cone come e meee ce eens nec ene cones cone 171 
Fig. 8. Cardinal view of right valve. 
8a. Right valve. Natural size. 
MYTILARCA CHEMUNGENSIS ..---- 2-2 22-202 -- ene cone cone cone cece oe ce een cee nnn one sane cnee 168 
Fig. 9. Right valve. Natural size. 
SANGUINOLITES ? GRACILIS..- .- -- 2 -- 2. 22 = cen coe cons wees ene cence mene wsen ence cscs cecc cece 175 
Fig. 10. Right valve. Natural size. 
