TREES AND SHRUBS OF MASSACHUSETTS. 415 



Vitis cesHvalis (Summer Grape). Several varieties of this species have 

 been noticed ; some of which have been described as separate 

 species. 



Vitis riparia (River Grape). On Wcstfield River and in Worcester 

 County. 



Ampelopsis quinquefoUa (Virginia Creeper). Common. 



XXXI.— RHAMNACE^ : The Buckthorn Family. 



Bhamnus catharticus (Common Buckthorn). Found near Boston; prob- 

 ably introduced from Europe. 

 Ehamnus alnifoUus (Alder-leaved Buckthorn). In moist grounds. 

 Ccanothus Americamcs (New Jersey Fern). A low, bushy shrub; com- 



XXXII.— CELASTRACEiE: The Staff-Tree Family. 



StapJiylca trifolia (Three-leaved Bladder Xut). A tall shrub or small 



tree. 

 Celastrus scandens (Staff-Tree). A twining shrub. 



XXXIIL— ACERACE^: The Maple Family. 



Acer rubrum (Red Maple). Abundant in swamps and low grounds. 

 Acer casyearpum (White Maple). Sandy or gravelly banks of clear 



streams throughout middle and western parts of State. 

 Acer soccharinum (Sugar Maple). Common; easily cultivated and 



very valuable. 

 Acer Pennsylvanicum (Striped Maple; Moose Wood). Abundant in 



middle and western parts of State and in Essex County. 

 Acer spicatum (Mountain Maple). A small tree grown in rocky places. 



XXXIV.— ANACARDIACE^ : The Sumac Family. 



Rlius trylihina (Staghorn Sumac). A tall shrub, sometimes a small tree 

 25 feet high, and 4 to 5 inches in diameter. 



Elms glabra (Smooth Sumac.) In barren fields and by the side of 

 woods, sometimes overspreading considerable tracts in neglected 

 fields. 



Bhm copalUna (Dwarf Sumac). On very rocky hills and roadsides, 

 usually 3 to 5 feet high, in rare instances 18 to 20, and 4 to 5 inches 

 in diameter. 



Rhus venenata (Poison Sumac.) In swamps, 8 to 10 feet high, and in 

 rare cases 15, and 2 to 3 inches diameter. Some persons are not 

 affected by the poison of this plant, and opposite effects are some- 

 times produced on different members of the same family. It is 

 thought that a varnish analogous to that obtained from the varnish- 

 yielding sumac of Japan could be prepared from this plant, and 

 some experiments tend to confirm this belief. 



Rhus toxicodendron (Poison Ivy). A clinging plant, less poisonous than 

 the preceding. 



Rhus aromatica (Fragrant Sumac.) Near the western border of the 

 State. 



XXXV.— XANTHOXYLACE^ : The Prickly Ash Family. 



Xanthoxylum Americanum (Prickly Ash). Found only in one place on 

 a southern slope in Medford. 



