CLASSIFICATION OF ANGIOSPERMS. 357 



The leaves of vvintergreen (Gaultheria procumbens) are the 

 source of true oil of wintergreen, which consists almost entirely 

 of methyl salicylate. It contains a small quantity of an alcohol 

 and an ester giving the characteristic odor. The same principles 

 probably also occur in several other species of Gaultheria (Fig. 



171)- 



The poisonous principle andromedotoxin is found in a number 



of species of Rhododendron, Leucothoe, and Pieris. This prin- 

 ciple is a powerful emetic and one of the most toxic principles 

 known. It probably occurs in the nectar of the flowers of Kalmia 

 and Rhododendron, being the cause of the poisonous properties 

 of the honey from this source. The leaves of several species of 

 laurel (Kalmia) contain considerable quantities of this principle, 

 and are poisonous to cattle. 



The plants of the genus Gaylusaccia are small shrubs distin- 

 guished by having an inferior, berry-like drupe with ten loculi. 

 To this genus belong the huckleberries, as black huckleberry 

 {G. resinosa) ; blue huckleberry {G. frondosa) ; and dwarf huckle- 

 berry {G. dumosa). The latter plant grows in sandy swamps 

 in both the United States and Canada and the fruit ripens in 

 May and June. The fruits of the other two species ripen in 

 July and August. 



The plants belonging to the genus Vaccinium vary from very 

 small shrubs to tree-like shrubs and the fruit is an inferior. 

 5-locular berry with numerous seeds. The blueberries or bilber- 

 ries (whortleberries) are the fruits of several species of Vacci- 

 nium. The low bush blueberry (V. pennsyhanicum) yields the 

 berries which ripen in June and July, while the high bush blue- 

 berry (V. corymbosum) furnishes the fruits which are found in 

 the market in July and August. 



The bilberry of Europe, Vaccinium Myrtillus, a plant growing 

 in Northern Europe and Asia and the Western United States and 

 Canada, is said to destroy Bacillus typhosus and B. Coli, an 

 infusion of the dried berries being used for this purpose. The 

 leaves of this plant contain ericolin and kinic acid. 



Cranberry is the fruit of several species of Vaccinium which 

 are sometimes grouped in a separate genus, Oxycoccus. There 

 are two principal species : The large or American Cranberry ( V. 

 macro car pum) in which the berries are ovoid or oblong and the 



