is a genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of about 300 species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 within the buttercup family Ranunculaceae
Ranunculaceae are a family of about 1700 species of flowering plants in about 60 genera, distributed worldwide....

. Their garden hybrids have been popular among gardeners
Gardening is the practice of growing and cultivating plants. Ornamental plants are normally grown for their flowers, foliage, or overall appearance; useful plants are grown for consumption , for their dyes, or for medicinal or cosmetic use...

 beginning with Clematis × jackmanii
Clematis × jackmanii
Clematis × jackmanii is the first of the modern hybrid large-flowered clematises of gardens. It is a climber with large violet-purple blooms, still among the most familiar climbers seen in gardens...

, a garden standby since 1862; more hybrid cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...

s are being produced constantly. They are mainly of Chinese and Japanese origin. Most species are known as clematis in English, while some are also known as traveller's joy a name invented for the sole British native, C. vitalba
Clematis vitalba
Clematis vitalba is a shrub of the Ranunculaceae family.-Description:Clematis vitalba is a climbing shrub with branched, grooved stems, deciduous leaves, and scented greeny-white flowers with fluffy underlying sepals...

by the herbalist John Gerard
John Gerard
John Gerard aka John Gerarde was an English herbalist notable for his herbal garden and botany writing. In 1597 he published a large and heavily illustrated "Herball, or Generall Historie of Plantes", which went on to be the most widely circulated botany book in English in the 17th century...

, virgin's bower for C. viticella
Clematis viticella
Clematis viticella or "Virgin's Bower", is a species of flowering plant in the buttercup family; it is native to Europe. The climber was the first clematis imported into English gardens, where it was already being grown in 1569 by Hugh Morgan, Apothecary to Queen Elizabeth, the "Virgin Queen"...

, old man's beard, applied to several with prominent seedheads, leather flower or vase vine for the North American Clematis viorna.
The genus name is from Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...

 clématis, a climbing plant,most probably a periwinkle.