VERBENACE^E. (VERVAIN FAMILY.) 339 



2. RUlSIiIjIA, 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 DIPTERACANTHUS) 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. Cilibsa, Pursh. Hirsute with soft whitish hairs ( 1 - 3 high) ; leaves 

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

 in the axils ; tube of the corolla ( 1' - 1' 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.}. Rich soil, Pennsylvania to Wisconsin, and 

 southward. July - Sept 



ORDER 70. VERBENACE^E. (VERVAIN FAMILY.) 



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

 corolla, and didynamous stamens, the 2 -^-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. VERBEXE.E. 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. PHRYME^E. 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 5-cleft. 



