GENUS 3. 



DOGBANE FAMILY. 



21 



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



Perennial branching herbs, with opposite entire leaves, and small white or pink flowers 

 in terminal and sometimes axillary corymbed cymes. Calyx 5-parted, the segments acute. 

 Corolla urceolate to campanulate, the tube bearing within 5 small appendages alternate with 

 the stamens, the limb S-lobed. Stamens inserted on the base of the corolla; anthers sagit- 

 tate, connivent around the stigma and slightly adherent to it. Disk S-lobed. Ovary of 2 

 carpels; ovules numerous in each carpel; stigma ovoid, obtuse, obscurely 2-lobed. Follicles 

 slender, elongated, terete. Seeds numerous, small, tipped with a long coma. [Greek, dogbane.] 

 About 1 1 species, of the north temperate zone, most abundant in North America. Type species : 

 Apocynum androsaemifolium L. 

 Corolla campanulate, not angled, 4" 4H" long, pink, its lobes widely spreading or recurved. 



i. A. androsaemifolium. 

 Corolla urceolate to short-tubular, or narrowly campanulate, angled, i>"-3/<2" long, greenish, 



white, or faintly pink, its lobes a little spreading, or erect. 



Corolla narrowly campanulate, 2 1 / 2 "-3 1 / 2 " long, lobes nearly equal the tube. 2. A. medium. 

 Corolla urceolate to short-tubular, i l / 2 "-3" long, lobes much shorter than the tube. 

 Calyx-lobes ovate, much shorter than the corolla tube. 3. A. Milleri. 



Calyx-lobes lanceolate, about as long as the corolla-tube. 

 Leaves and cymes glabrous, or sparingly pubescent. 



Leaves all narrowed at the base and distinctly petioled ; flowers greenish ; plant rather 



bright green. 4. A. cannabinum. 



At least the lower leaves sessile, and mostly rounded or subcordate at the base ; plant 



pale glaucous green ; flowers white. 5. A. sibiricum. 



Leaves, cymes, and often the whole plant densely pubescent. 6. A. pubescens. 



I. Apocynum androsaemifolium L. 

 Spreading Dogbane. Fig. 3376. 



Apocynum androsaemifolium L. Sp. PI. 213. 1753. 

 Syst. Ed. 10, 946. 1759. 



A. di-vergens Greene, Leaflets i : 56. 1904. 



Rootstock horizontal ; stem i "-4 high ; branches 

 broadly spreading, mostly glabrous. Leaves ovate 

 or oval, acute or obtuse and mucronate at the 

 apex, rounded or narrowed at the base, glabrous 

 above, pale and usually more or less pubescent 

 beneath, 2,'-^' long, i'-2$' wide; petioles 2"-^" 

 long; cymes loose; pedicels 2"-$" long, subulate- 

 bracted at the base ; flowers about 4" broad ; calyx- 

 segments shorter than the tube of the pinkish 

 corolla; corolla-lobes revolute; follicles about 4' 

 long, narrowed at the apex. 



In fields and thickets, Anticosti to British Colum- 

 bia, south to Georgia, Missouri, Nebraska and Ari- 

 zona. Ascends to 3500 ft. in Virginia. Honey-bloom. 

 Bitter-root or -dogbane. Rheumatism-wood. Wild 

 ipecac. Wandering milk-weed. Western wall-flower. 

 Fly-trap. June-July. Linnaeus inadvertently failed 

 to affix a binominal specific name in the first edition 

 of his "Species Plantarum," but corrected this six 

 years later. 



2. Apocynum medium Greene. Intermediate Dogbane. 

 Fig- 3377- 



Apocynum medium Greene, Pittonia 3 : 29. 1897. 



Apocynum spcciosnm G. S. Miller, Proc. Biol. Soc. Wash. 13: 83. 

 1899. 



Rootstock horizontal ; stem stout, 4 high or less, the branches 

 ascending, glabrous. Leaves oblong to oval or elliptic, mucronulate, 

 ascending, 2^-4' long, somewhat pubescent beneath; petioles 

 2"-4" long; cymes terminal, compact; pedicels \\"-2.\" long; 

 flowers erect; calyx-segments ovate, about half as long as the 

 5-angled corolla-tube; corolla white or pinkish, 2\"~z\" long, 

 urceolate-campanulate, its lobes acutish, somewhat spreading, 

 nearly as long as the tube; follicles $'-4' long. 



Fields and hillsides, Quebec to the District of Columbia, west to 

 Iowa. June-Aug. 



