Skip to main content
Select Source:

Cooksonia hemispherica

Cooksonia hemispherica (order Rhyniopsida) Extremely primitive plant, a few centimetres high, from the Upper Silurian and Lower Devonian. Members of the family did, however, possess an epidermis (protective outer layer) and stomata (specialized pores) to control the passage of gases. They also had an underground rooting portion, the rhizome, and they branched dichotomously. C. hemispherica is the first representative of the Rhyniaceae, and is known from the Silurian of Europe. See also PSILOPHYTALES; and RHYNIA.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Cooksonia hemispherica." A Dictionary of Earth Sciences. . Encyclopedia.com. 22 May. 2018 <http://www.encyclopedia.com>.

"Cooksonia hemispherica." A Dictionary of Earth Sciences. . Encyclopedia.com. (May 22, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/cooksonia-hemispherica

"Cooksonia hemispherica." A Dictionary of Earth Sciences. . Retrieved May 22, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/cooksonia-hemispherica

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

Cooksonia hemispherica

Cooksonia hemispherica (family Rhyniaceae) An extremely primitive plant from the Upper Silurian and Lower Devonian belonging to a family whose members did, however, possess an epidermis and stomata to control the passage of gases. They also had an underground rooting portion, the rhizome, and they branched dichotomously. C. hemispherica is the first representative of the Rhyniaceae, and is known from the Silurian of Europe.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Cooksonia hemispherica." A Dictionary of Plant Sciences. . Encyclopedia.com. 22 May. 2018 <http://www.encyclopedia.com>.

"Cooksonia hemispherica." A Dictionary of Plant Sciences. . Encyclopedia.com. (May 22, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/cooksonia-hemispherica-0

"Cooksonia hemispherica." A Dictionary of Plant Sciences. . Retrieved May 22, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/cooksonia-hemispherica-0

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.