400 ACANTHACEAE. 



Ovary 1-celled, with 2 parietal placentae expanded into broad surfaces, or 

 2-4-celled by the intrusion of tbe placentae or by false partitions; ovules 

 anatropous; style slender; stigma 2-lobed or 2-lamellate. Seeds com- 

 pressed; endosperm none; embryo large; cotyledons fleshy, flat; radicle 

 short, straight. Three genera and about 12 species, mainly tropical. 



1. MAETYNJA L. Sp. PI. 618. 1753. 



■Coarse glandular-pubescent and viscid strong-scented herbs, with long- 

 petioled leaves, and large flowers in short terminal racemes. Calyx 1-2- 

 bracteolate at the base, eampanulate, inflated, deciduous. Corolla funnelform- 

 ' eampanulate. Anthers gland-tipped, their sacs divergent. Ovary 1-celled, the 

 2 parietal placentae intruded and expanded in the center of the cavity into 

 broad surfaces bearing the ovules in 1 or 2 rows. Fruit an incurved beaked 

 loculicidally 2-valved capsule, the exocarp somewhat fleshy, the endoearp 

 fibrous, woody, crested below or also above, 4-celled by the extension of the 

 placentae. Seeds numerous, tuberculate. [Named for John Martyn, 1693- 

 1768, profesor of botany at Cambridge, England.] About 8 species, natives 

 of America. Type species: Martynia annua L. 



1. Martynia annua L. Sp. PI. 618. 1753. 



Martynia diandra Glox. Obs. Bot. 14. 1785. 



Viscid-pubescent, branched, 5-8 dm. high, the stem and branches rather 

 stout. Leaves thin, flaccid, opposite, long-petioled, ovate-orbicular, 8-15 cm. 

 long, sinuate-dentate, palmately veined, acute at the apex, cordate at the base ; 

 racemes" short-peduneled, several-flowered; pedicels 1-2 cm. long, slender, 

 thickening and recurved in fruit; calyx very deeply 5-cleft, about 1.5 cm. long, 

 its segments acute ; stamens 2 ; corolla pink, or nearly white, 3-5 cm. long, 

 its rounded lobes purple-blotched; capsule obliquely o\oid, compressed, 2-2.5 

 cm. long, viscid, tipped mth a hooked beak about 3 mm. long. 



Waste places, Nassau, New Providence : — Cuba to Porto Hico, St. Thomas and 

 Antigua ; Martinique and Bequia ; continental tropical America. Sjiali.-fkuited 

 Maettnia. 



Family 15. ACANTHACEAE J. St. Hil. 



Acanthus Family. 



Herbs, or some tropical genera shrubs or small trees, with opposite 

 simple estipulate leaves, and irregular, or nearly regular, perfect flowers. 

 Calyx inferior, persistent, 4-5-parted or 4^5-cleft, the sepals or segments 

 imbricated. Corolla gamopetalous, nearly regularly 5-lobed, or 2-lipped. 

 Anther-bearing stamens 4, didynamous, or 2 only ; anther-sacs longitu- 

 dinally dehiscent. Disk annular, or cup-like. Ovary 2-celled; ovules 2-10 

 in each cavity, anatropous or amphitropous ; style filiform, simple; stigmas 

 1 or 2. Capsule dry, 2-eelled, loculicidally elastieally 2-valved. Seeds not 

 winged, borne on curved projections (retinacula) from the placentae, the 

 testa close, mostly roughened, often developing spiral threads and mucilage 

 when wetted. About 175 genera and 2,000 species, natives of temperate 

 and tropical regions. 



Herbs or shrubs. 



Stamens 4, didynamous. 



Caulescent herbs or shrubs. 



Flowers in densely bracted terminal spikes. 1. Blcchum. 



Flowers solitary or cymose, 2. Rucllia. 



Acaulescent herbs with spicate iiowers. 3. Gerardla. 



