This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Annual diffuse pubescent slender and fragile herbs, with alternate or opposite mostly pinnatihd or lobed leaves. Flowers white, blue or variegated, solitary, peduncled, lateral or terminal. Calyx deeply 5-cleft or 5-parted, with a reflexed or spreading appendage in each sinus. Corolla campanulate or rotate-campanulate, mostly longer than the calyx, usually with 10 small appendages within at the base, the lobes convolute in the bud. Stamens included; anthers ovate or oblong. Ovary 1-celled with placentae similar to those of Hydrophyllum; styles partly united; ovules 2-12 on each placenta. Capsule 2-valved. Seeds 1-4. [Greek, grove-loving.]
About 10 species, natives of North America, mostly Californian. Type species: Nemophila bhacelioides Nutt.
Ellisia microcalyx Nutt. Trans. Am. Phil. Soc. (II.) 5:
191. 1833-37. Nemophila microcalyx F. & M. Sert. Petrop. pl. 6. 1846.
Stems very slender, diffuse, branched, 2-15' long. Leaves membranous, petioled, l'-2 1/2' long, pinnatifid or pinnately divided into 3-5 obovate cuneate or oblique, obtuse 2-3-dentate or -lobed, approximate or confluent segments, the upper all alternate, the lowest opposite; peduncles slender, 4 '-12" long, opposite the leaves, shorter than or equalling the petioles; flowers white or blue, 1 1/2"- 2" long; appendages in the sinuses of the calyx minute; calyx scarcely enlarged in fruit; ovules 2 on each placenta; corolla-appendages obsolete or none; anthers oval; capsule about 1 1/2" in diameter, much longer than the calyx, 1-2-seeded.
In woods, Virginia to Florida, west to Arkansas and Texas. April-June.