MACLOSKIE : ASCLEPIADACE^E. 663 



Family 91. APOCYNACE^:. Dogbane Family. 



Plants usually with milky juice, simple exstipiilate leaves, and regular 

 5-merous, sympetalous flowers with inferior perianth, and 5 epipetalous 

 stamens, alternating with the corolline divisions. Ovary, of 2 distinct 

 carpels, or syncarpous and 2-1 -celled. Fruit of 2 follicles or drupes. 

 Seeds often comose, with sparing endosperm. 



Species exceeding 1,000, chiefly tropical. 



GRISEBACHIELLA Lorentz. 



Flowers axillary, solitary. Calyx hard, thick, persistent, deeply 5- 

 partite, the parts connate at base, concave, obtuse, externally pubescent 

 or subglabrous. Glands in base of calyx lobes. 



G. HIERONYMI Lorentz. 



Woody shrub, scarcely i meter high ; branching, flexuose or angulose, 

 old branches glabrous, terete. Leaves decussate, ovate, acuminate, i- 

 nerved, acute, glabrous, rigid, coriaceous, yellow-green, caducous, 12 by 

 6 mm. Petiole 2 mm. Flowers very small, on a very short peduncle, 

 with a minute bract, deflexed. 



N. Patagon. (Roca Expedition to Rio Negro. Quid? Eng. & Prantl, 

 iv, 2, 189). 



Family 92. ASCLEPIADACE^E. Milkweed Family. 



Herbs or shrubs, with milky juice, and mostly opposite, exstipulate 

 leaves. Flowers 5-merous, regular, sympetalous, with a 5-parted crown 

 inside the corolla. Stamens 5, epipetalous, and alternating with the corol- 

 line divisions ; anthers connivent around discoid, united stigmas, or synan- 

 therous ; the pollen cohering in waxy masses. Ovary superior, with 2 

 carpels and styles, united by the stigma. Seeds plumose ; with scanty 

 endosperm. 



Species nearly 2,000, widely distributed, especially in warm climates. 



KEY TO THE GENERA. 



(The Patagonian genera all have the pollen in 2 wax-like masses, hanging by transfer-organs.) 

 A. Crown none. Corolla divided more than half-way. Stigma elongating to 2 filiform branches. 



I. Mitostigma, p. 664. 

 A2. Crown ringform, fastened to the throat of the rotate or campanulate corolla. Gynostegium 



subsessile. Corolla smooth inside. Shrubs or half shrubs. 2. Turrigcra, p. 664. 



AT,. Crown fastened on the gynostegium, its tips free, or only basally united. Corolla valvate in the bud. 



