knowlton] TERTIARY PLANTS OF NORTH AMERICA. 159 
Pecopteris constricta Font. Potomac Fl., p. 8(3, pi. xx, f. 1, 2, 4, 1889. 
Potomac formation: Fredericksburg, Virginia. 
Pecopteris Dunkeri Schiinp. = Cladophlebis Dunkeri. 
Pecopteris microdonta Font. Potomac FL, p. 85, pi. xix, f. 8; xx, f. 
5,11,1881). 
Potomac formation : Fredericksburg and near Dutch Gap Canal, 
Virginia. 
Pecopteris montanensis Font. Proc. IT. S. Nat. Mus., vol. xv, p. 492, 
pi. lxxxiii, f. 1, la, 1892. 
Kootanie: Great Falls, Montana. 
Pecopteris nebraskana ? lleer- Cyathites nebraskana. 
Pecopteris ovatodentata Font. Potomac FL, p. 85, pi. xv, f. 8; xxii, 
f. 12; xxii, f. 1, 1889. 
: Fredericksburg and Dutch Gap Canal, Virginia. 
Pecopteris pachyphylla Font. Potomac FL, p. 88, pi. xxvi, f. 4, 5, 
1889. 
Potomac formation: Fredericksburg, Virginia. 
Pecopteris (Phegopteris) sepulta Newby. Proc. U. S. Nat. Mus., 
vol. v, p. 503, 1882 [1883]. 
Eocene: Green Eiver, Wyoming. 
Pecopteris (Pteris?) socialis Heer. Fl. Foss. Arct., vol. vi, pt. ii, 
p. 34, pi. vii, f. 4, 1882; Font., Potomac FL, p. 87, pi. xxi, f. 7, 1889. 
Potomac formation : Near Brooke, Virginia. 
Pecopteris strictinervis Font. Potomac FL, p. 84, pi. xiii, f. 6-8; 
xix, f. 9; xx, f. 3; xxii, f. 13; clxx, f. 5, 6, 1889. 
Potomac formation : Fredericksburg, Virginia ; Baltimore, Mary- 
land. 
Knoxville beds: Tehama County, California. 
Pecopteris Torelli Heer=Osmunda Doroschkiana. 
Pecopteris virginiensis Font. Potomac FL, p. 82, pi. viii, f. 1-7; ix, 
f. 1-6; xxiv, f. 2; clxix, f. 3, 1889. 
Potomac formation: Near Dutch Gap Canal, Fredericksburg, 
Potomac Run, near Brocke, and near Telegraph Station, Vir- 
ginia; Baltimore, Maryland. 
Pecopteris sp., Dn. Geol. Surv. Canada, Kept, of Progress for 1872-73, 
Appen. i, p. 70, 1873. 
Cretaceous : Hornby Island, British Columbia. 
Pecopteris sp., Dn. Trans. Koy. Soc. Canada, vol. i, sec. iv, p. 25, 
1882 [1883]. 
Upper Cretaceous: Baynes Sound, Vancouver Island. 
PERSEA Gartner. Fr. and Sem., vol. iii, p. 222, 1805. 
Persea Borbonia (L.) Spreng. Hollick, Bull. Torr. Bot. Club, vol. xix, 
p. 332, 1892. 
Lauras carolhieiisis Michx. Lesquereux, Am. Jouru. Sci v vol. xxvii, p. 363, 
1859; Geol. Tenn., p. 426, pi. K, f. 10, 1869. 
Pleistocene?: Somerville, Fayette County, Tennessee. 
Miocene"?: Bridgeton, New Jersey. 
