202 HYPERICACEAE 



Key to the Shrubby Species 



Leaves completely sessile ; flowers with 5 styles, capsules 



5-celled H. Kalmianum 



Leaves on very short but distinct petioles; styles 3, capsules 



3-celled . H. prolificum 



HYPERICUM KALMIANUM Linnaeus 

 Kalm's St. John's-Wort 



Kalm's St. John's-Wort, fig. 51, is a low shrub seldom more 

 than 12 to 30 inches high, with ascending branches and branch- 

 lets bearing entirely sessile, opposite leaves. The leaves are 

 oblanceolate to linear-oblong, 1 to 2 inches long by about ^ 

 inch wide, obtuse or acute at the apex and rounded at the base. 

 The lower surface is glaucous, and the upper surface is covered 

 with minute black dots. 



The flowers, which appear in July and August, are arranged 

 in small, compound cymes at the end of branchlets. The yellow 

 flowers are ^ to 1 inch wide and stand on short pedicels. The ^ 

 fruit, which matures in the autumn, is a 4- to 6-celled, ovoid 

 capsule about one-third inch long, which contains numerous 

 oblong seeds pitted on the surface in lengthwise rows. 



Distribution. — Kalm's St. John's-Wort is a shrub which 

 prefers sandy situations and it ranges, where habitats are 

 suitable, from Quebec to Wisconsin and south into New York 

 and Illinois. Its Illinois distribution is remarkable, in that it 

 is limited to the region directly adjacent to Lake Michigan, 

 in the northeast corner of the state, to a relatively small terri- 

 tory in the western part of the Ozarks, and to Pope County, 

 in the southern part of the state. There apparently are no inter- 

 vening situations in which this plant is found. 



HYPERICUM PROLIFICUM Linnaeus 



Shrubby St. John's-Wort 



The Shrubby St. John's-Wort, fig. 51, is a low and usually 

 widely branching shrub, which reaches a height of 2 to 31/^ 

 feet. Its ascending or erect, 2-edged branches bear numerous 

 opposite, very shortly petioled leaves, which are linear-oblong 

 to oblanceolate and ^ to 4 inches long by l4 to ^ inch wide. 

 They are obtuse at the apex, the main nerve running out 



