Narrative

Phacelia genus is native to the New World including both North and South America. These plants are herbs with blue or white flowers in terminal cymes or racemes. There are 158 species and 64 subspecies growing in greater North America, including Puerto Rico and the U.S. Virgin Islands.

Waterleaf Family (Hydrophyllaceae) is a small family of about two hundred and fifty to three hundred species of wide distribution. As of 1994, there were 233 species in about 16 genera either native to or established in greater North America.

Tubiflora Order of plants is comprised of a large number of families that are characterized by having tube-like flowers. Several of the families have asymmetrical flowers with various lip and lobe configurations, while others have symmetrical flowers. The convention is to refer to the corolla divisions as lips, and to refer to the extensions at the end of the lips as lobes. This large order can be divided into two groups of families: those families with flowers with radial symetry and those famlies with flowers with bi-lateral symetry.

Dicots (Dicotyledoneae Class) are the predominant group of vascular plants on earth. With the exception of the grasses (Monocots) and the Conifers (Gymnosperms), most of the larger plants that one encounters are Dicots. Dicots are characterized by having a seed with two outer shell coverings.

Some of the more primitive Dicots are the typical hardwood trees (oaks, birches, hickories, etc). The more advanced Dicots include many of the Composite (Aster) Family flowers like the Dandelion, Aster, Thistles, and Sunflowers. Although many Monocots reach a very high degree of specialization, most botanists feel that the Dicots represent the most advanced group of plants.

Seed plants (Phylum Embryophyta) are generally grouped into one large phylum containing three major classes: the Gymnosperms, the Monocots, and the Dicots. (Some scientists separate the Gymnosperms into a separate phylum and refer to the remaining plants as flowering plants or Angiospermae.)

For North American counts of the number of species in each genus and family, the primary reference has been John T. Kartesz, author of A Synonymized Checklist of the Vascular Flora of the United States, Canada, and Greenland (1994). The geographical scope of his lists include, as part of greater North America, Hawaii, Alaska, Greenland, Puerto Rico, and the Virgin Islands.

Kartesz lists 21,757 species of vascular plants comprising the ferns, gymnosperms and flowering plants as being found in greater North America (including Alaska, Hawaii, Greenland, Puerto Rico and the Virgin Islands.

There are estimates within the scientific world that about half of the listed North American seed plants were originally native with the balance being comprised of Eurasian and tropical plants that have become established.