368 APOCYNACEAE 



2. Amsonia tomentosa Torr. & Frem. Woolly Amsonia. Fig, 3824. 



Amsonia tomentosa Torr. & Frem. Second Rep. 316. 1845. 



Amsonia hrevifolia var. tomentosa Jepson, Man. Fl. PI. Calif. "68. 1925. 



Stems several from the woody base, 25-35 cm. high, simple or branched above, herbage 

 hoary-tomentose throughout including the calyx. Leaves lanceolate to ovate, acute to acumi- 

 nate, 2-5 cm. long, short-petioled ; calyx-lobes 4-6 mm. long, very slender and weak ; corolla 

 whitish, turning bluish in age, the tube clavate, constricted at the summit, about 10 mm. long, 

 the lobes oblong-ovate, 5 mm. long, 7-nerved; follicles 3-6 cm. long, more or less torulose; 

 seeds usually pointed at both ends. 



Rocky slopes and bajadas. Lower Sonoran Zone; base of the San Bernardino Mountains, Mojave Desert, 

 and northern Colorado Desert, California to Nevada, Arizona, and southern Utah. Type locality: "probably 

 west of the Rocky Mts." April-June. 



2. VINCA L. Sp. Pi. 209. 1753. 



Erect or trailing- herbs, or some species slightly woody, with opposite entire leaves, 

 and large flowers solitary in the axils. Calyx 5-parted, the segments narrow, acuminate. 

 Corolla salverform, the lobes oblique, convolute in bud, the tube pubescent within, the 

 throat constricted. Stamens 5, alternate with the lobes included. Disk of 2 large glands 

 alternating with the 2 carpels. Ovules several in each carpel; style simple, filiform; 

 stigma annular and penicillate at apex. Follicles 2, cylindric, erect or spreading, several- 

 seeded. Seeds oblong-cylindric, truncate at each end, without coma. [The ancient Latin 

 name.] 



An Old World genus of about 12 species. Type species, Vinca major L. 



1. Vinca major L. Periwinkle. Fig. 3825. 



Vinca major L. Sp. PI. 209. 1753. 



Trailing slightly woody vines, rooting freely, the flowering stems or branches erect, 2-3 dm. 

 high. Leaves bright green and glabrous, ovate, cordate at base, obtuse or acute at apex, 2-3 cm. 

 long ; petioles 5-20 mm. long, often ciliolate ; pedicels slender, 3-5 cm. long ; calyx-lobes subulate, 

 about 1 cm. long; corolla blue or violet, the tube 15-20 mm. long, the lobes as long as the tube or 

 longer and nearly as broad at the obliquely subtruncate apex ; follicles cylindric, somewhat torulose, 

 4 cm. or more in length. 



Shaded or partly shaded places, Upper Sonoran and Transition Zones; escaped from cultivation and becoming 

 naturalized in many localities in the Pacific States. Native of the Mediterranean Region. Often but erroneously 

 called myrtle. March-July. 



3. APOCYNUM L. Sp. PI. 213. 1753. 



Perennial herbs with opposite entire leaves and corymbose cymes of small white or 

 pink flowers. Calyx 5-parted, the segments lanceolate, acute. Corolla urceolate to cam- 

 panulate, 5-lobed, the tube bearing 5 small appendages alternate with the stamens. Stamens 

 borne on the base of the corolla-tube ; anthers sagittate, connivent around the stigma 

 and slightly adherent to it. Disk present, 5-lobed. Ovary of 2 carpels, each bearing 

 numerous ovules ; stigma ovoid, obtuse, obscurely lobed. Fruit of 2 slender elongated 

 terete follicles. Seeds numerous, small, tipped with a long conspicuous coma. [Greek, 

 meaning dogbane.] 



As delimited by Woodson (Ann. Mo. Bot. Card. 17: 1-172. 1930.) Apocynum is a North American genus of 

 7 species. Type species, Apocynum cannabiniim L. 



Corolla barely exceeding the calyx, the lobes erect; leaves ascending. 



Corolla spherico-cylindric, about as broad as long; leaves distinctly petioled; coma of seeds 20-30 mm. long. 



1. A, cannabinum. 

 Corolla tubular-cylindric, distinctly longer than broad; leaves sessile or essentially so, the lower often 

 amplexicaul; coma of seeds 15-20 mm. long. 2. A. sibcricunt satignutn. 



Corolla at least twice the length of the calyx, campanulate or cylindric, the lobes spreading or recurved. 

 Leaves spreading; corolla cylindric, 4-5 mm. long. 3. A. medium floribundutn. 



Leaves drooping; corolla campanulate or cylindric, at least 3 times as long as the calyx. 



Corolla campanulate, 5-10 mm. long; cymes rarely axillary as well as terminal; pods pendulous. 



4. A. androsaemifolium. 

 Corolla cylindric, 4-6 mm. long; cymes usually axillary as well as terminal; pods erect. 



5. A. pumilum. 



1. Apocynum cannabinum L. Common Dogbane or Indian Hemp. Fig. 3826. 



Apocynum cannabinum L. Sp. PI. 213. 1753. 



Apocynum cannabinum var. glaberrimum A. DC. Prod. 8: 439. 1844. 



Apocynum Bolanderi Greene, Leaflets Bot. Obs. 2: 175. 1912. 



Stems erect or ascending, 3-6 dm. high, branched above, the branches ascending often op- 

 posite, herbage glabrous throughout. Leaves ascending, distinctly petioled, ovate to lanceolate 

 or oblong-lanceolate, acute to rounded at both ends, conspicuously apiculate at apex, 4-12 cm. 

 long, 1-4 cm. wide, pale beneath ; cymes terminal ; bracts minute, scarious ; calyx-lobes scarious. 



