Feb., 1912.] The Mallows of Ohio. 465 



THE MALLOWS OF OHIO. 



Mary B. Linnell. 



MALVACEAE Mallow Family. 



Mucilaginous, innocent herbs or shrtibs with alternate, pal- 

 mately- veined leaves and small deciduous stipules. Flowers 

 hypogynous, regular, often large and showy, usually bisporangiate ; 

 calyx usually of 5 sepals more or less united,. often with bracts at 

 the base; corolla of 5 petals, convolute; andrecium of numerous 

 stamens, the filaments united into a tube around the gynecium 

 and also united with the base of the petals; ovulary with several 

 cavities, styles united below, distinct above; stigmas usually as 

 many as the cavities of the ovulary. Fruit a capsule with several 

 cavities; the carpels falling away entire or else loculicidally 

 dehiscent. 



Synopsis of Genera. 



I. Stamen-column anther-bearing at the tip; carpels 5-20 in a ring around 



a prominent central axis from which they separate when ripe. 



A. Carpels 1-seeded. 



1. Flowers bisporangiate. 



(1) Stigmas linear, on the inner face of the styles. 



a. Involucre of 1-3 bracts. 



(a) Carpels beakless; petals obcordate. Malva. 



(b) Carpels beaked; petals truncate. Callirrhoe. 



b. Involucre of 6-9 bracts. Althaea. 



(2) Stigmas terminal, capitate. Sida. 



2. Flowers monosporangiate, diecious. Napaea. 



B. Carpels 2 — several seeded. AbutUoti. 



II. Stamen-column naked at the .5-toothed tip; carpels forming a loculi- 



cidal capsule. 

 A. Involucre of many bracts. Hibiscus. 



Key. 

 1. Flowers without an involucre. 2. 



1. Flowers with involucre below the calyx. 4. 



2. Leaves not lobed; flowers bisporangiate. 3. 



2. Leaves deeply lobed; flowers diecious. Napaea. 



3. Leaves broadly cordate, abruptly acuminate. Abutilon. 



3. Leaves ovate-lanceolate, acute. Sida. 



4. Stamen-column anther-bearing below the entire or 5-toothed summit; 



involucre of numerous linear bracts. Hibiscus. 



4. Stamen-column anther-bearing at the summit. 5. 



5. Involucre of 6-9 bracts united at the base. Althaea. 

 0. Involucre usually of 3 free bracts. 6. 



6. Carpels beakless; petals obcordate; leaves divided or only slightly 



lobed. Malva. 

 6. Carpels beaked; petals truncate; leaves parted or divided. Callirrhoe. 



Malva L. 



Pubescent or glabrate herbs with dentate, lobed, or dissected 

 leaves, and axillary or terminal, solitary or clustered flowers. 

 Carpels beakless, arranged in a circle, indehiscent; cavities of 

 ovulary several or numerous, 1-ovuled; seed ascending. 



