28 CATALOGUE OF THE CRETACEOUS AND [bull. 152. 
ACERATES Mlsson. Act. Ac. Holm., p. 345, 1831. 
Acerates sp., Hollick in Newby., Fl. Amboy Clays, p. 124, pi. xxxii, 
til-, xli, f. 4, 5, 1895 [1896], 
Amboy clay : South Amboy, New Jersey. 
ACERITES Viviani. Mem. Soc. Geol. d. France, vol. i, p. 131, 1833. 
Acerites meuispermifolia Lx.=Menispermites inenispermifolia. 
Acerites multiformis Lx. Fl. Dak. Gr., -p. 156, pi. xxxiv, f. 1-9, 1892. 
Dakota group : Kansas. 
Acerites negundifolium Dn. Trans. Roy. Soc. Canada, vol. viii, sec. 
iv, p. 8(3, f. (in text) 19, 1890. 
Eocene?: Stump Lake, British Columbia. 
Acerites pristinus Newby. Later Extinct Flora, p. 15,1868; 111. Cret. 
and Tert. PI., pi. v, f. 4, 1878. 
Dakota group : Blackbird Hill, Nebraska. 
ACORUS Linneaus. Gen. ed., i, p. 104, 1737. 
Acorus afiinis Lx. Aun. Rep. U. S. Geol. and Geogr. Surv. Terr., p. 
410, 1873 [1874]. [Not afterwards recognized.] 
Green River group?: Florissant, Colorado. 
Acorus brachystachys Heer. K. Sven. Vetenskaps-Akad. Handl., 
vol. viii, no. 7, p. 51, pi. viii, f. 7, 8, 1870 [in Fl. Foss. Arct. ii, abt. 
iii, 1871]; Lx., Ann. Rept. U. S. Geol. and Geogr. Surv. Terr., p. 288, 
1871 [1872] ; Tert. FL, p. 105, pi. xiv, f. 12-15, 1878. 
Denver group ? : Sedalia, Colorado. 
Laramie group ?: Carbon, Wyoming. 
Acorus calamus L. Lesquereux, Am. Journ. Sci., vol. xxvii, p. 365, 
1859. 
Pleistocene: Banks of Mississippi River near Columbus, Ken- 
tucky. 
ACROSTICHOPTERIS Fontaine. Potomac Fl., p. 106, 1889. 
Acrostichopteris cyclopteroides Font. Potomac FL, p. 109, pi. xciv, 
f. 8, 1889. 
Potomac formation: Near Dutch Gap Canal, Virginia. 
Acrostichopteris densifolia Font. Potomac FL, p. 107, pi. xciv, f. 
4; clxx, f. 11; clxxi, f. 2, 6; clxxii, f. 13, 1889. 
Potomac formation: Baltimore, Maryland; Dutch Gap Canal, 
Virginia. 
Acrostichopteris longipennis Font. Potomac FL, p. 107, pi. clxx, 
f. 10; clxxi, f. 1, 5, 7, 1889. 
Potomac formation : Baltimore, Maryland. 
Acrostichopteris parcelobata Font. Potomac FL, p. 108, pi. xciv, f. 
6, 7, 11, 14, 1889. 
Potomac formation: Dutch Gap Canal, and near Potomac Run, 
Virginia. 
Acrostichopteris parvifolia Font. Potomac FL, p. 108, pi. xciv, f. 5, 
9, 10, 12 ; clxxi, f. 3, 4 ; clxxii, f. 14, 1889. 
Potomac formation: Baltimore, Maryland; Dutch Gap Canal, 
Trents Reach, Virginia. 
