504 



LAMELLIBRANCHIA TA. 



Pleurorhynchus, Phillips, syn. for Conocar- 



dium. 



antiquum, see Conocardium antiquum. 

 attenualum, see Conocardium attenuatum. 

 crassifrons, see Conocardium crassifrons. 

 cuneus, see Conocardium cuneus. 

 trigonale, Hall, see Conocardium subtrig- 



onale. 



vomer, see Conocardium vomer. 

 Posidonia, Bronn, see Posidonomya. 

 alata, see Posidonomya alata, 

 alveata, see Grammygia alveata. 

 arcuuta, see Grammysia arcuata. 

 clathrata, see Posidonomya clathrata. 

 distans, see Posidonomya distans. 

 lirata, see Prtracyclas lirata. 

 moorei, see Posidonomya moorii. 

 perstriata, see Posidonomya perstriata. 

 POSIDOXOMYA, Bronn, 1837, Leth. Geogn. 

 [Ety. Poseidon, a mythological name; 

 Mya, a genus.] Shell thin, obliquely 

 oval, subtruncate at one end, equivalve, 

 compressed, concentrically furrowed, 

 hinge-line short and straight, edentu- 

 lous. Type P. becheri. 

 alata, Hall, 1843, (Posidonia (?) alata,) 

 Geo. 4th Dist. N. Y., p. 72, and Pal. 

 N. Y., vol. 2, p. 87, Clinton Gr. 



ambigua, Winchell, 1863, 

 Proc. Acad. Nat. Sci., 

 p. 10, Marshall Gr. 

 clathrata, Lea, 1853, (Posi- 

 donia clathrata,) Jour. 

 Acad. Nat. Sci., 2d ser., 

 vol. 2, p. 205, Coal Meas. 

 devonic ' a F Wa l co tt, 1885, 

 Monogr. U. S. Go. Sur. 

 vol. 8, p. 179, Devonian. 

 distans, Lea, 1853, (Posidonia distans,) 

 Jour. Acad. Nat. Sci., 2d ser., vol. 2, p. 

 205, Coal Meas. 

 fracta, Meek, 1875,. Ohio Pal., vol.2, p. 



333, Coal Meaa. 

 fragosa, see Lunulicardium 



fragosum. 



Uevis.Walcott, 1885,Monogr. 

 U. S. Geo. Sur., vol. 8, p. 

 178, Devonian. 

 mesambonata, Winchell, 

 1862, Proc. Acad. Nat. Sci., 

 p. 420, Marshall Gr. Fio. 



moorii, Gabb, 1859, (Posi- Posi f racta nya 

 donia moorei,) Proc. Acad. 

 Nat. Sci., p. 297, Coal Meas. 

 perstriata, Lea, 1853, (Posidonia perstri- 

 ata,) Jour. Acad. Nat. Sci., 2d ser., vol. 

 2, p. 205, Coal Meas. 

 rhomboidea, Hall, 1852, Pal. N. Y., vol. 2, 



p. 284, Niagara Gr. 

 romingeri, Winchell, 1862, Proc. Acad. 



Nat. Sci., p. 420, Marshall Gr. 

 striata, Stevens, 1858, Am. Jour. Sci., vol. 



25, p. 265, Coal Meas. 

 whiteana, Winchell, 1862, Proc. Acad. 



Nat. Sci., p. 420, Marshall Gr. 

 PR-ECAROIUM, Barrande, 1881, Syst. Sil. de 

 la Boheme, vol. 6, p. 141. [Ety. prse, 

 before ; Cardium, a genus.] Equivalve, 

 inequilateral, elliptical or trigonal ; 



onomya bech- 



beaks prominent, incurved; surface 

 radiated, and concentrically lined; 

 posterior to the beaks a 

 small area carries a series 

 of vertical nearly parallel 

 teeth. . 



vetustum, Hall, 1843, (Car- 

 dium vetustum,) Geo. Rep. 

 4th Dist. N. Y., p. 245, and 

 Pal. N. Y., vol. 5, p. 427, 

 Portage Gr. 

 PRISCONAIA, Conrad, 1867, Am. Jour. 

 Conch., vol. 3. [Ety. proper name.] 

 Equivalve, inequilateral, and distin- 

 guished from Anthracosia, which it much 

 resembles, by having lateral teeth. Type 

 P. ventricosa. 



ventricosa, Conrad, 1867, Am. Jour. 



Conch., vol. 3, Coal Meas. 

 PROMACRUS, Meek, 1871, Am. Jour. Conch., 

 vol. 7, p. 4. [Ety. pro, forward; mak- 

 ros, long.] Similar to tianguinolites ; 

 anterior end much produced, narrowly 

 rounded ; posterior end produced, ob- 

 liquely truncate ; beaks appreesed ; 

 cardinal margin nearly straight behind 

 the beaks, and declining in front; 

 umbonal slope angular, extending to 

 the basal extremity; surface concen- 

 trically lined, and sometimes plicated 

 anteriorly ; ligament external. Type 

 P. andrewsi. 



andrewsi, Meek, 1871, Am. Jour. Conch., 

 vol. 7, p. 4, Waverly Gr. 



cuneatus, Hall, 1870, (Pholadella cune- 

 ata,) Prelim. Not. Lam. Shells, p. 66, 

 and Pal. N. Y., vol. 5, p. 510, Waverly Gr. 



missouriensis, see Sanguinolites missouri- 

 ensis. 



nasvius, see Sanguinolites nasutus. 

 PRORHYNCHUS, Hall, 1885, Pal. N. Y., vol. 

 6, p. 48. [Ety. pro, forward ; rhynchos, 

 beak.] Left valve the larger and more 

 gibbous ; anterior end truncate, angular 

 or nasute at the antero-dorsal ex- 

 tremity ; posterior end broad, margin 

 truncate or broadly rounded ; beaks 

 low ; cardinal line straight, extending 

 the entire length of the dorsal margin, 

 and alate at both ends ; umbonal slope 

 subangular; surface concentrically 

 lined; strong lateral tooth, ligament 

 external. Type P. quad rat um. 



angulatum, Hall, 1885, Pal. N. Y., vol. 5, 

 p. 493, Chemung Gr. 



nasutum, Hall, 1885, Pal. N. Y., vol. 5, 

 p. 493, Chemung Gr. 



quadratum, Hall, 1883, (Palseanatina 

 quadrata,) Pal. N. Y., vol. 5, p. 492, 

 Chemung Gr. 



PROTITYRIS, Meek, 

 1869, Proc. Acad. 

 Nat. Sci. Phil., p. 

 172. [Ety. pro, for- 

 ward ; thyris, an 

 orifice.] Equi- 

 valve, inequilat- 

 eral, extremely elongate; cardinal 

 and basal margins subparallel ; anterior 



FIQ. 900. Frothy ris 

 'meeki. 



