THE DOGBANE FAMILY 



APOCYNACE^ Lindley 



HIS family contains about 130 genera comprising some 1050 species of 

 perennial herbs, shrubs, vines and a few tropical trees; they are widely 

 distributed, but especially abimdant in the tropics. They abound in 

 acrid, often milky juices, which make some of the plants of great 

 importance as producers of India rubber; many are very poisonous, but few of 

 them are in general use as medicines, the most important drug being the powerful 

 heart sedative, Strophanthus, the seed of Strophanthus Kombe Ohver, a native of 

 tropical Africa; many are highly ornamental and found in great variety in con- 

 servatories. 



The Apocynaceae have alternate or opposite, simple leaves without stipules. 

 The flowers are perfect, regular, 5-parted and variously clustered. The calyx is 

 inferior, persistent, its lobes imbricated ; the 5 lobes of the corolla are often twisted ; 

 the stamens are of the same number as the lobes of the corolla, alternate with 

 them, and joined- to its tube; the anthers are. 2-celled; the ovary is superior, i- 

 ceUed with 2 parietal placentas, or 2 -celled. The fruit usually consists of 2 foUicles 

 or drupes ; the seeds are often appendaged ; the endosperm is fleshy, the cotyledons 

 straight. 



One arborescent species has become naturalized in our area. 



OLEANDER 



GENUS NEEIDM LINN^US 

 , Species Neriom Oleander Linnaeus 



]LEANDER is a well-known conservatory and house plant, native of 

 the Mediterranean region; it has become naturalized in fields and 

 roadsides in the Gulf States, often becoming a tree 10 meters in height. 

 The branches are slender, erect, forming a narrow head. The 

 bark is about 6 mm. thick, close, slightly furrowed and dark brown. The twigs 

 are slightly angular, somewhat pithy, smooth, Ught green, becoming brown and 

 marked by prominent leaf scars. The leaves are opposite, numerous, leathery, 

 narrowly eUiptic or linear-elliptic, 6 to 15 cm. long, sharp or taper-pointed at both 

 ends, entire margined, dark green and shining above, paler, with prominent mid- 

 rib, and numerous straight nerves beneath; the leaf -stalk is very short, stout and 

 channelled. The flowers are in terminal, compoimd cymes; the 5 calyx-lobes are 



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