A-POCYNACE^E. (DOGBANE FAMILY.) 349 



ORDER 84. APOCYNACEJE. (DOGBANE FAMILY.) 



Plants with milky acrid juice, entire (chiefly opposite) leaves without sti- 

 pules, regular 5-merous and 5-androus flowers ; the o lobes of the corolla 

 convolute and twisted in the bud; the filaments distinct, inserted on the corolla, 

 and the pollen granular ; the calyx entirely free from the two ovaries, which 

 are usually quite distinct (and forming pods), though their styles or stig- 

 mas are united into one. Seeds amphitropous or anatropous, with a large 

 straight embryo in sparing albumen, often bearing a tuft of down (comose). 

 Chiefly a tropical family (of acrid-poisonous plants), represented in our 

 district by three genera. 



Synopsis. 



1 AMSONIA. Seeds naked. Corolla with the tube bearded inside. Anthers longer than the 

 filaments Leaves alternate 



2. FORSTERONIA. Seeds comose. Corolla funnel-form, not appendaged. Filaments slen- 

 der. Calyx glandular inside. Leaves opposite. 



8. APOCYNUM. Seeds comose. Corolla bell-shaped, appendaged within. Filaments short, 

 broad, and flat. Calyx not glandular. Leaves opposite. 



1. AMSONIA, Walt. AMSONIA. 



Calyx 5-parted, small. Corolla with a narrow funnel-form tube bearded in- 

 side, especially at the throat ; the limb divided into 5 long linear lobes. Sta- 

 mens 5, inserted on the tube, included : anthers obtuse at both ends, longer than 

 the filaments. Ovaiies 2 : style 1 : stigma rounded, surrounded with a cup-like 

 membrane. Pods v ( follicles) 2, long and slender, many-seeded. Seeds cylindri- 

 cal, abrupt at both ends, packed in one row, naked. Perennial herbs, witn 

 alternate leaves, and pale blue flowers in terminal panicled cymes. (Said to be 

 named for a Mr. Charles Amson.) 



1. A. Tafoernaemoiltfiiia, Walt. Leaves ovate-lanceolate, rather 

 obtuse at the base, short-petioled ; tube of the corolla above hairy outside. (A. 

 latifolia, Michx.) Damp grounds, Illinois (Mead, &c.), Virginia 1 ? and south- 

 ward. May. 



A. CILIATA, with linear leaves, and A. SALiciF6LiA, with lanceolate leaves 

 may be expected in Virginia. 



2. FORSTERONIA, Meyer. FORSTERONIA. 



Calyx 5-parted, with 3-5 glands at its base inside. Corolla funnel-form, not 

 appendaged ; the limb 5-lobed. Stamens 5, inserted on the base of the corolla, 

 included : filaments slender : anthers arrow-shaped, with an inflexed tip, adher- 

 ing to the stigma. Pods (follicles) 2, slender, many-seeded. Seeds oblong, 

 with a tuft of down. Twining plants, more or less woody, with opposite 

 leaves and small flowers in cymes. (Named for Mr. T. F. Forster, an English 

 botanist.) 



1. F. l if form is, A. DC. Nearly herbaceous and glabrous ; leaves oval- 

 lanceolate, acuminate, thin ; calyx-lobes taper-pointed ; corolla pale yellow 

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