POP 'LUS — POPLAK. 255 



witli long hairs. A tree, 20 to 50 feet high, with smooth, grccnish-whito 

 bark. Loaves roiiuiUsli-cordute, acuiuinate, serrate, sniootli both sitles, 

 downy on the margiuH ; i)etioleH long, slender, laterally compressed, so 

 that the gentlest breeze suffices to keep the leaves constantly agitated. 



Habitat. — lu woods and copses ; common. 



Populus balsamifera Liunt'. — Ikttffum Poplar, Tarmahnn. 



Dcscrqifion. — Scales of the catkins dilated, slightly liairy. A tree, 40 to 

 80 feet high. Loaves ovate, acuminate, sei-rate Avith ai)prcssed teeth, 

 smooth both sides, green above, white and reticulate-veiny beneath. In 

 spring the buds arc covered with an aromatic resin. 



Habitat. — In moist soil, Northern New England to Wisconsin and nortli- 

 ward. 



A variety of this species (/'. caudicans Aiton — P>nhn of Cilcad) differs in 

 having the leaves l^roader and somewhat cordate ; it is common in cultiva- 

 tion as a shade tree. 



Pa?Vx (W(1. — Of P. tremuloides, the bark ; of P. balsamifera the resin- 

 oua exudation of the buds — neither is official. 



ConxtitHi'.nti<. — The bark of all si)ecies of pojilar contains a crystalline 

 principle; termed popitJin, closely resembling salicin. The resin of the 

 balsam poj)lar does not dift'er materially in composition from other aro- 

 matic resins. 



r reparations. — Poplar bark is commonly administered in decoction or 

 infusion. The resin of the balsam poplar is readily separated from the 

 buds by boiling them in water ; it may then be dissolved in alcohol, and 

 administered in this form, or a tincture of tlie entire buds may be em- 

 ployed. 



Medical Properties and Uses. — Poplar bark is a bitter tonic, acting like 

 willow-bark, and i^ossessing feeble antiperiodic properties. It is little 

 used. 



Poplar balsam is reputed tonic and stimulant. It was formerly used 

 to a limited extent in pharmacy, to prevent ointments becoming rancid. 



CONIFER/E. 



CJiaracfer of the Order. — Monoecious, rarely dioecious, trees or shrubs ; 

 flowers in catkins, destitute of calyx and corolla ; stamens inserted on the 

 axis of the catkin under the scales, or the anther-cells are sessile on the 

 scales themselves ; ovules and seeds naked. Leaves mostly awl-.shaped or 

 needle-shaped. Juice commonly resinous. 



A large order, dispersed over all parts of the globe, most al)undant 

 in temperate regions, but extending also to the tropics and friqid zones. 

 It comprises three well-mai"ked sub-orders, namely : Abietinede, Pine 

 Family; Cupressineae, Cypress Farnihj ; Taxineae, Yew Family. 



