124 JOURNAL AND PROCEEDINGS. 



vestigation whether this form of poison-ivy does not also abound 

 there. The berries, ripe in October, are whitish or dun-colored, 

 with striate stones, and look somewhat like bunches of small grapes. 

 — a similarity, however, which need give rise to no error, as a glance 

 at the leaves shows them to be compound, whereas in the grape they 

 are swiple. Taken altogether, this Rhus is one of the handsomest 

 shrubs imaginable when in bloom, but is unfortunately one of the 

 most dangerous. Rhus Venenata has been thought to be identical 

 with the Rhus Vernicifera of Japan, and when incisions are made 

 into its bark there is a copious flow of viscid fluid, yellowish at first, 

 but soon changing to a deep black, which, when boiled, makes a 

 fine varnish. The poisonous properties of this tree are said to be 

 more powerful than those of Rhus Toxicodendron, persons exposed 

 to its influence being more apt to suffer, and more severely. I have 

 known several cases of poisoning due to this plant being mistaken 

 for the common elder, an error which could never arise were the 

 fact borne in mind that both varieties of elder, found in this coun- 

 try, have the margins of the leaves toothed, whereas in Rhus Venen- 

 ata they are entire. In addition, the elders have dense masses of 

 flowers, and a fruit which, when ripe, is either red or black, while 

 the form of poison-ivy has slender, scattered bunches of flowers, and 

 a fruit whitish' in color when mature. Rhus Venenata is not very 

 common in Canada, but is occasionally found in the western part 

 of Ontario. The recorded localities are Weston, Port Colborne^ 

 Niagara Falls, Hatchley and London, Ont. 



Rhtis Toxicodendron may be made to include Rhus radicans, as 

 botanists are now pretty well agreed that it is but a variety of the 

 former, its differing form and characters, viz., more entire leaflets 

 and high climbing stem, being dependent on the circumstances of 

 its habitat. Rhus Toxicodendron was first described in 1635 by 

 Cornutus in his work on Canadian plants, as a species of ivy. The 

 Indians were well aware of its properties, and its effects were men- 

 tioned by Kalur and other travellers in North America. Poison 

 oak, poison ivy, poison vine, poison creeper, and sometimes poison 

 mercury, are names applied to it. It is very common throughout 

 Canada from Nova Scotia to the Saskatchewan at Fort Edmonton, 

 and is also recorded as occurring in woods near Yale, British Colum- 

 bia. It is commonest in fertile and low grounds, but will thrive in 

 barren and elevated places, and attaches itself to any bodies in its 



