218 American Midland Naturalist Monograph No. 4 



Honeysuckle {Lonicera L.) 



Field Guide to the Species 



Upright shrubs; flowers in pairs, rarely soHtary; leaves distinct. 



Corollas yellow or yellowish, regular or nearly so, the lobes distinctly shorter 

 than the tubes. 



Bracts below flowers large, more or less enveloping the ovaries, becoming 



red and conspicuous in fruit; ftuits purple-black 



I . L. involucrata. 



Bracts below flowers small, usually awl-shaped; fruits black or red. 



Ovaries enclosed by sac-like united bractlets which becomes juicy and 

 colored in fruit, appearing as a single black berry. 



Corollas usually finely hairy outside; found in western parks 



2. L. coerulea. 



Corollas usually smooth outside; found on Isle Royale 



3. L. villosa var. 



Ovaries slightly joined below, appearing as twin berries, red when 

 ripe. 



Leaves somewhat pointed at the tips, the margins thinly hairy; 

 corolla-tubes strongly swollen on one side at the base; 

 eastern species 4. L. canadensis. 



Leaves smooth or slightly hairy on margins at very base; corolla- 

 tubes slightly swollen on one side at the base; western 

 species 5. L. utahensis. 



Corollas dark purple-red, 2-lipped, the tubes mostly shorter than the lobes 



- 6. L. conjiigialis. 



Bushy or high climbing shiubs with trailing or twining branches; flowers borne in 

 circles along the stems near the ends or in head-like clusters; upper leaf 

 pairs usually joined into saucer-like structures. 



Low shrubs with stems trailing along the ground; corollas slightly 2-lipped, the 

 tubes swollen on one side above the base. 



Leaves 2 to 4 inches long; found in Northwest ..7. L. ciliosa. 



Leaves ^4 to 2 inches long; found in Southwest 8. L. arizonica. 



Bushy or climbing shrubs with twining branches; corollas strongly 2-lipped, 

 the tubes swollen on one side at the base. 



Leaves dull green, hairy on both sides; corollas glandular outside 



9. L. hirsula. 



Leaves green above, paler or whitish below, smooth, or hairy only below; 



corollas smooth or sparingly hairy outside. 



Leaves oblong, 2 to 4 inches long; eastern species 10. L. dioica. 



Leaves roundish to egg-shaped or elliptic-oblong; % to 1 inch long; 



western species II. L. intemipia. 



I. Bearberry Honeysuckle, Black Twinberry (Lonicera involu- 

 crata (Rich.) Banks), fig. 13 L — Widely branching shrub 1 to 6 feet high 

 with 4-angIed branches; leaves narrowly egg-shap>ed to oblong, pointed at the 

 tips, with a prominent midrib, the margins not toothed, 2 to 5 inches long, 

 dark green; flowers yellow, about ^ to % inch long, tubular, scarcely 2-Iipped, 

 with a swollen pouch at base of tube, borne in pairs and surrounded at the 

 base by a cup-like involucre composed of two broad leaf-like bracts; berries 



