506 CONTEIBUTIONS FEOM THE NATIONAL HERBAEIUM. 



4. Apocynum. laurinum Greene, Pittoiiia 5: 64. 1902. 



Type locality: Organ Mountains, New Mexico. Type collected by Wooton 

 (no. 113). 

 Range: Mountains of eouthern New Mexico. 

 New Mexico: Organ Mountains; Ruidoso Creek. 



5. Apocynum hypericifolium Ait. Hort. Kew. 1: 304. 1789. 

 Type locality': North America. 



Range: British America to Ohio and New Mexico. 



New Mexico: Mesilla Valley. River valleys, in the Lower and Upper Sonoran 

 zones. 



6. Apocynum viride Woot. & Standi. Contr. U. S. Nat. Herb. 16: 159. 1913. 

 Tyte LOCALITY': Gilmores Ranch on Eagle Creek, White Mountains, Lincoln County, 



New Mexico. Type collected by Wooton and Standley (no. 3451). 



Range: New Mexico. 



New Mexico: Farmington; Cedar Hill; Las Vegas; Pecos; Reserve; ^Miite and 

 Sacramento mountains. Wet ground, in the Upper Sonoran and Transition zones. 



7. Apocynum angustifoUum Wooton, Contr. U. S. Nat. Herb. 16: 159. 1913. 

 Tyte locality: Gila River bottom near CUff, Grant County, New Mexico. Type 



collected by Metcalfe (no. 132). 



Range: Southwestern New Mexico. 



New Mexico: CUff; Mimbres; Lower Plaza; Eagle Creek. Along streams, in the 

 Upper Sonoran Zone. 



A very distinct species because of its very narrow bright green leaves, nearly all 

 of them acute at the base. 



115. ASCLEPIADACEAE. Milkweed Family. 



Herbaceous perennials, erect or twining, mostly with milky juice; leaves simple, 

 alternate, opposite, or whorled, exstipulate, mostly entire; flowers perfect, regular, 

 mostly umbellate; calyx hypogynous, the tube very short or none, imbricated in 

 bud; corolla 5-merous, campanulate, urceolate, rotate, or funnelform, the lobes com- 

 monly reflexed; a 5-lobed crown (corona) borne between the corolla and stamens 

 and adnate to one or both of them; stamens 5, adnate to the corolla usually near its 

 base, monadelphous or distinct; anthers converging around the stigmas, sometimes 

 united to each other, the sacs tipped with an inflexed or erect scarious membrane 

 or not appendaged at the top, sometimes appendaged at the base; pollen in Avaxy 

 masses (pollinia) connected with the stigma in pairs; pistil of 2 carpels; styles 2, 

 with a single peltate discoid stigma; fruit a pair of several to many-seeded follicles; 



seeds comose. 



key to the genera. 



Pollinia horizontal or nearly so; stigma sharply 5-angled, 



depressed ; twining vine 1. Vincetoxicum (p. 507). 



Pollinia pendulous; stigmas various; stems twining or 

 straight. 

 Crown double, the outer a shallow ring, the inner 

 consisting of 5 fleshy hoodhke scales; twining 



vines 2. Philibertella (p. 507). 



Crown single; erect, ascending, or procumbent herbs. 



Corolla lobes erect-spreading during anthesis; 



hoods of the crown pendulous or saccate 



at the base, curved upward, obtuse, 



crested within, at least in the upper part. 3. Asclepiodora (p. 508). 

 Corolla lobes reflexed during anthesis; hoods 

 various. 



