Ptycho. 



836 



plate 5, fi^. 3. ConeGophdlites trilineahcs Ford, 1871, 1873, 1875, 

 Amer. Jour. Sci. Vol. 2, p. 33; Vol. 6, p. 135; Vol. 9, p. 205.' 

 Conocoryphe, Ford, 1880, Amer. Jour. Sci. Vol. 19, p. 152). 

 Walcott, Bulletin 30, U. S. G. S. page 203, plate 27, %. 1, one 

 of Emmons' original specimens now in Am. Mus. Nat. Hist. N. 

 Y. city; fig. la, 15, enlarged twice, Ford's drawings of speci- 

 mens found at Troy; Ic, copy of Emmons' original figure in 

 Amer. Geol. plate 1. fig. 7. Lower Cambrian {Georgian) Con- 

 glomerate limestone beds near Troy ; also below Quebec; also 

 in Washington Co., N. Y. Z. C, 



Ptycoparia vulcanus. 



Aa 



( Conocephalites vulcanus^ Billings, 



Tnl ^^^^' ^^^^- ^^' II. 9^2, fig. 



7^^*^ 357; Pal. Foss.I,p.l4,fig. 

 17; Geol. Vt. 18G3, 286, 

 fig. 296.) Walcott, Bul- 

 I letin No. 30, U. S. G. S. 

 page 1^8, plate 26, fig. 4, 

 compressed spec, from Parker's quarry; fig. 4a, more perfect 

 one from '' Red sandrock " east of Highgate Springs. Lower 

 Cambrian {Georgian) formation, in Vermont. L. C. 



Ptychophyllum kn^ppi. See page 887. 



Ptychopteria beeeheri, Hall, Pal. N. Y. Vol. V i. 1884, 



143,pl. 

 85, ^g. 

 21, an 

 entire 



, ■ , eft 



Fal.N.y.,V (•,p.f//3,f)l..8'5". valve • 



J 



22, right valve ; somewhat resembles P. trigonalis ; right valve 

 like P. alata, but left valve very unlike it; distinguishing 

 characters, its large rhomboidal form, extreme gibbosity and 

 arcuation of left valve. From Upper Chemung at Warren, 

 Pa. Randall's specimens 9613, 9616, 9617, 9618, 9620, 9621, 

 wrongly labelled Allorisma, TIlLg, 



Ptychopteria elongata, Hall, Pal. N. Y. Vol. V i, 1884, 

 page 141, pi. 85, fig. 10, hinge view; 11, ventral view; 12, large 

 right valve; 13, left valve of 10; surface marked by fine radi- 



( Continued on page d38.) 



