152 ELEME^'TS OF BOTANY. 



HELIANTHEMUM. 



Herbs, somewhat woody at the base ; stem branching ; 

 flowers often of 2 forms, the one with large and showy petals, 

 the other small and inconspicuous, both perfect ; stamens 

 few or numerous ; style short or wanting, stigma capitate or 

 3-lobed. 



1. H. Carolinianum Michx. Carolina Rock-rose. Peren- 

 nial from a woody base; stems villous, 0-12 in. high; leaves short- 

 petioled, lanceolate, or the lower obovate, acute, denticulate, margins 

 not revohite ; flowers mostly terminal, all large and petaliferous, 

 yellow, 1 in. wide; stamens many; capsule many-seeded. March- 

 April. Dry, sandy soil. 



2. H. Canadense (L.) Michx. Frost-weed. Perennial from a 

 woody base ; stems hoary-pubescent, erect, widely branched, 10-20 

 in. high ; leaves lanceolate or elliptical, downy, or smooth above, 

 entire, margin revolute ; flowers axillary, of 2 kinds, the larger 1 in. 

 wide, solitary, the smaller appearing later, apetalous, clustered; 

 sepals acute,, pubescent, the inner larger, much longer than the 

 depressed-globose caj)sule. April-June. Dry, sterile soil. 



82. VIOLACEiE. VIOLET FAMILY. 



Herbs, often acaulescent ; leaves simple, basal or alternate, 

 stipulate ; flowers usually solitary, perfect, irregular ; sepals 

 5, persistent ; petals 5, irregular, the lower one usually sac- 

 cate or spurred ; stamens 5, hypogynous, connivent ; style 

 single ; ovary 1-celled, with 3 parietal placentae, 3-valved, 

 many-seeded. 



VIOLA. 



Annual or perennial, acaulescent or with a decumbent stem ; 

 leaves nearly entire or much divided ; flowers single, long- 

 peduncled, oblique ; sepals prolonged at the base ; lower petal 

 spurred ; filaments of the two upper stamens proloilged above 

 the anthers ; style usually bent and stigma beaked ; many 

 species producing fertile, apetalous flowers on short pedun- 

 cles late in the season. 



