Herbarium Genus Names

What's in a name?

What's wrong with the good old common names that one can pronounce? Fireweed, cougar, Florida panther and horsetail are all easier to remember than Erechtites hieracifolia, Felis concolor, Felis concolor coryi and Equisetum, but there are a few problems.

I grew up in the mid-west where fireweed brought to mind a brilliant fuchsia spike of flowers ((Epilobium angustifolium) which carpets the forest floor after a fire. When I came to South Carolina I almost got into an argument with a native who tried to tell me that this bright green plant with sanecio-like cream colored flowers was fireweed. Then I looked at the habitat. It was growing at the disturbed edge of a forest. The common name was coined for a plant that occupied recently disturbed ground and not because of the brilliance of its flowers. The name in both cases was a good one, but, the plants were not the same species.

The cougar, panther, Florida panther, mountain lion, and puma are local names for the same species referred to by scientists as Felis concolor. Isolated breeding populations with some morphological differences are designated as subspecies (varieties). Thus the small isolated population of Florida panthers is officially named Felis concolor ssp coryi. The category ÒformÓ is generally used to recognize sporadic variations with little taxonomic significance.

Horsetails (Equisetum sp.) plants whose fossil record dates back over 200 million years are also known as scouring rush. Growing at the edges of sandy bottomed streams the cell walls of these plants contain high levels of silicon. The pioneers used these tough stems as mother nature's brillo pads. Thus, the common name, scouring rush.

So we must resort to the scientific name which few can pronounce and fewer can spell. Coined by Linnaeus in 1735, the two word name includes the genus and species epithet. The complete classification of the multi-flower rose is as follows:

Kingdom: Planta - organisms with tissue specialization and photosynthesis
Division: Anthophyta - flowering plants
Class: Dicots - Plants with flower parts in 4s and 5s and broad leaves
Order: Rosaceae - the rose family including Raspberries, roses, and potentillas
Genus: Rosa - the roses
Species: multiflora - rose with many flowers

It's as if you placed all the organisms in the world on a table and began separating them into smaller and smaller piles until you were left with many small piles of closely related organisms. The first subdivision would be into a plant pile and a squirming pile of animals. The plant pile could then be subdivided into those plants containing flowers and groups without flowers. Further subdivisions would separate flowering plants into groups with more and more similar flowers until you were left with piles of plants that were so closely related that they could breed and produce fertile offspring. These would be organisms of the same species.

The scientific name for the multi-flowering rose is Rosa multiflora. If you were to look it up in Radford Ahles, and Bell you would see it written Rosa multiflora Thunberg. Thunberg was the author of the name. Some scientific names are followed by several authors. ie Melilotus officinalis (L.)Lam. The yellow sweet clover was first described by Linnaeus (L.) but the name was later modified by Lamarck (Lam.). A detailed description of the organism is written when it is first described (in Latin of course) and it is accompanied by a voucher herbarium collection (the type specimen).

But what about horses and asses which when bred produce sterile mules? Or what about lichens which are actually composed of two separate organisms (algae and fungi) and thus do not go through sexual reproduction? The scientific definition of a species touted so confidently in the previous paragraph doesn't work at all. Well there is always this one: A species is whatever a competent taxonomist says it is.

For more information:

  • Jones, Samuel B. & Arlene E. Luchsinger. Plant Systematics. Mcgraw-Hill, N.Y. 1978.
  • Radford, Albert E., Harry E. Ahles & C. Ritchie Bel. Manual fo the Vascular flora of the Carolinas, Univ. of N.C. Press, Chapel Hill. 1968.