CATALOGUE OF PLANTS. 141 443 R. Britannica, L. GREAT WATER DOCK. Common in swamps and wet places back of sea beaches; less C.B.S., common in wet ground farther inland, Long Pond meadows; Rc+ Somesville (Redfield). Abund. Bay Chaleur (M) GR. Cacl. BR 444 R. salicifolius, Weilm. WHITE DOCK. RaR. Mx. Sea beaches; frequent, especially on Cranberry Isles and C.B.RduR. wester and northern shores of the Island. Also Northeast Bonav G. Harbor; Sea Wall (Rand); Bar Harbor (W. H. Manning). BR.- 445 R. verticillatus, L. SWAMP DOCK. Rare. Marsh on Northeast Creek; Norwood Cove (Rand). 446 R. CRISPUS, L. CURLED DOCK. Mx. Common in cultivated and waste ground. Naturalized from C.B.P.S. Europe. Natl Cacl+ BR. GR. Perct Wx. 447 R. OBTUSIFOLIUS, L. BITTER DOCK. Waste places; rare. Somesville (Rand); Bar Harbor (W. B.Q.W.X, H. Manning). Adventive from Europe. Natl BR. Perct YK+ 448 R. ACETOSELLA, L. FIELD SORREL. Mx. T A very common weed in fields and waste places. Naturalized B.P.Q.S.C from Europe. X.Caol. BR. Perct GIB. GR. W.X. D., 9C POLYGONUM, L. KNOTWEED. 449 P. aviculare, L. DOORWEED. Percl GIB. D. GR. Cacl+ BR GR. C.B.P.Q.S. A common weed about dwellings, by roadsides, etc. Vari- W. able; erect or prostrate. 450 P. Raii, Bab. Mx. T Stems long, straggling, prostrate; leaves bending towards C.RduX. the stem, elliptic-lanceolate, flat; ochreae lanceolate, acute, with Bie.Caol.FP few distinct simple veins, at length torn; nut smooth, shining, BR.YK+ exceeding the perianth. Resembling P. aviculare in habit, but P. maritimum in fruit. Filaments broader at the base. It varies with smaller leaves and flowers. Babington, Man. Brit. Bot. (4th ed.) 285. Common on sea beaches. This species has been often mistaken for P. maritimum, and so reported. So far as known, however, P. maritimum is not found within the