verbenace^e. (vervain family.) 339 



2. RUELLIA, L. (Dipteracanthus, Nees, & Ed. 2.) 



Calyx 5-parted. Corolla funnel-form, the spreading ample border almost 

 equally and regularly 5-cleft, convolute in the bud. Stamens 4, included, di- 

 dynamous: cells of the somewhat arrow-shaped anthers parallel and nearly 

 equal. Pod narrow, in our species (of the section Diptekacanthus) somewhat 

 flattened, contracted and seedless at the base, above 8-12-seeded. Seeds with 

 a mucilaginous coat, when wet under the microscope exhibiting innumerable 

 tapering short bristles, their walls marked with rings or spirals. — Perennials, 

 with rather large and showy blue or purple flowers, mostly in axillary clusters, 

 sometimes also with small flowers precociously close-fertilized in the bud. Calyx 

 often 2-bracteolate. (Named for the early herbalist, John Ruelle.) 



1. R. Cilidsa, Pursh. Hirsute with soft whitish hairs (1° -3° high); leaves 

 nearly sessile, oval or ovate-oblong (l'-2' long) ; flowers 1-3 and almost sessile 

 in the axils ; tube of the corolla (l'-l£' long) fully twice the length of the setaceous 

 calyx-lobes ; the throat short. (Dipteracanthus ciliosus, Nees.) — Dry soil, Mich- 

 igan to Illinois, and southward. June - Sept. 



2. R. str^pens, L. Glabrous or sparingly pubescent (l°-4°high); leaves 

 narrowed at the base into a petiole, ovate, obovate, or mostly oblong (2^' - 5' long) ; 

 tube of the corolla (about 1' long) little longer than the dilated portion, slightly 

 exceeding the lanceolate or linear calyx-lobes. (Dipteracanthus strepens, Nees.) — 

 Flowers 1 - 5 in each axil, rarely on a slender peduncle, usually almost sessile ; 

 sometimes many and closely crowded, then mostly fruiting in the bud, (when it 

 is D. micranthus, Engelm. §' Gr.). — Kich soil, Pennsylvania to Wisconsin, and 

 southward. July - Sept. 



Order 70. VEKBENACEjE. (Vervain Family.) 



Herbs or shrubs, with opposite leaves, more or less 2-lipped or irregular 

 corolla, and didynamous stamens, the 2-4-celled (in Phryma 1-celled) fruit 

 dry or drupaceous, usually splitting when ripe into as many 1-seeded inde- 

 hiscent nutlets ; differing from the following order in the ovary not being 

 4-lobed, the style therefore terminal, and the plants seldom aromatic or 

 furnishing a volatile oil. — Seeds with a straight embryo and little or no 

 albumen. — A large order in the warmer parts of the world, sparingly rep- 

 resented in cool regions. 



Tribe I. VERBENEiE. Ovary 2 - 4-celled, and with an erect anatropous ovule in each 

 cell : radicle inferior. 



1. Verbena. Flowers in spikes or heads. Calyx tubular. Fruit splitting into 4 nutlets. 



2. Lippia. Flowers in spikes or heads. Calyx short, 2-cleft. Fruit splitting into 2 nutlets. 



3. Callicarpa. Flowers in axillary cymes. Calyx .short. Fruit berry-like, with 4 nutlets. 

 Tribe II. PHR.YMEJE. Ovary 1-celled : ovule erect, orthotropous : radicle superior. 



4. Phryma. Flowers in slender spikes. Calyx cylindrical, 2-lipped. Fruit an achenium. 



1. VERBENA, L. Vervain. 



Calyx tubular, 5-toothed, one of the teeth often shorter than the others. Co- 

 rolla tubular, often curved, salver-form ; the border somewhat unequally o-cleft 



