Shrubby plants with glabrous subquadrangular stems, their tips densely covered with thick parallel cystoliths; leaf blades oblong- ovate, up to 30 cm. long and 13 cm. wide, short-acuminate at tip, rounded at base, pandurate, thin, entire or undulate, glabrous, the costa and lateral veins (about 12 pairs) moderately prominent espe- cially beneath, the cystoliths minute and inconspicuous; petioles about 3 mm. long, thick and glabrous; panicles very slender, axillary up to 30 cm. long and 8 mm. broad, the peduncle up to 10 cm. long, glabrous, sulcate, 1.25 mm. thick, the lowermost node of the rachis 4 cm. long, the others successively shorter toward the tip of the raceme, all sulcate, glabrous or sparingly hirtellous; flowers more or less secund, crowded in small slender spikes or panicles, several of these at each axil of the main rachis; bracts subtending the spikes or secondary panicles narrowly triangular, up to 3 mm. long and 0.3 mm. wide at base, subcarinate, narrowed to a slender tip, glabrous or hirtellous toward tip; bracts subtending the flowers subulate, about 1.25 mm. long, 0.25 mm. wide, gradually narrowed from base to a slender bluntish tip, carinate, sparingly hirtellous, the hairs rigid, ascending, 0.8 mm. long; bractlets similar but slightly longer; pedicels 1.5 mm. long, slender, glabrous; calyx 2.5 mm. long, the segments 5, lanceolate, 2 mm. long, 0.5 mm. wide near base, narrowed to a slender tip, sparingly hirtellous with rigid ascending hairs 0.32 mm. long, the costa evident but not prominent; corollas greenish white, about 5 mm. long, sparingly and finely pubescent, the tube subcylindric, 3.5 mm. long and 1 mm. broad at base, enlarged to 1.5 mm, from just above base to throat, the lips about 3 mm. long, the upper lip erect, oblong-ovate, about 1.5 mm. wide, minutely bilobed at tip, the lobes rounded, the lower lip more or less spreading, 1.5 mm. wide near base of the 3 lobes, these 1.5 mm. wide, 0.75 mm. long, rounded; stamens 3 mm. long, their filaments very slender, glabrous, the anthers glab- rous, the cells slightly superposed, attached vertically to a relatively broad connective, the upper cell 1.75 to 2 mm. long, the lower 1.5
mm. long and short-caudate; style slightly longer than the stamens; stigma minute and bilobate; ovary glabrous; capsules not seen.
Type in the U. S. National Herbarium, No. 2045413, collected in a shaded wet place in rather scrubby, brushy woods on white clay soil, 2 km. east of Barbacoas and just south of the Río Telembí, Depart- ment of Nariño, Colombia, 100 meters altitude, October 13, 1943, by F. R. Fosberg (No. 21244). Isotype: US.
CHOCó: Juntos de Tamaná, March 1853, Triana s.n. (K, Col). San Pablo, March 1853, Triana s.n. (K).
Justicia atacta has a strong superficial resemblance to a Pseuder- anthemum, having panduriform leaf blades and a long very slender inflorescence, the extremely small spicate or paniculate branches simulating the clusters of pediceled flowers in Pseuderanthemum. Yet a close examination of the flowers reveals superposed anther lobes, the lower one tailed, and no staminodes.
The specific epithet is from the Greek áraкros, meaning irregular or atypical.