22 MIDDLESEX FLORA. 



CELASTRACE^E. STAFF-TREE FAMILY. 



CELASTRUS, L. 



C. scandens, L. ROXBURY WAXWORK. CLIMBING BITTER- 

 SWEET. 

 Rather common. June. 



SAPINDACE^E. SOAPBERRY FAMILY. 



STAPHYLEA, L. 

 S. trifolia, L. BLADDER-NUT. 



Weston (Bigelow's PI. Bost.) ; not since reported in Middlesex, but 

 found (1886) in the adjacent town of Needham, in Norfolk Co. 

 May-June. 



^ESCULUS, L. 

 JE. HlPPOCASTANUM, L. HORSE-CHESTNUT. 



Propagates itself occasionally by seed. May-June. Int. from 



Asia via Eu. 



CARDIOSPERMUM, L. 

 C. Halicacdbum, L. 



Somerville (C. E. Perkins). Adv. from the Southwest. 



For description, see Wood's Bot. & PI. 

 ACER, Tourn. 

 A. Pennsylvanicum, L. STRIPED MAPLE. 



Concord (Minot Pratt) ; Ashby (L. L. Dame). Rare. May-June. 

 A. spicatum, Lam. MOUNTAIN MAPLE. 



Concord, int. from Wachusett by Minot Pratt; Ashby (L. L. 



Dame). The elevated region about Mt. Watatic seems to be the 



only county station where this maple grows naturally. June. 

 A. saccharinum, Wang. ROCK MAPLE. SUGAR MAPLE. 



Not abundant. Apr.-May. 

 A. dasycarpum, Ehrh. WHITE MAPLE. 



Lowell, Tewksbury, Bedford, et al. Not common native. March- 

 Apr. 

 A. rubrum, L, RED MAPLE. SWAMP MAPLE. 



Very common. Apr. 



POLYGALACE>E. MILKWORT FAMILY, 



POLYGALA, Tourn. 

 P. sanguinea, L. 



Common. July-Aug. 



