Pictures from Google Image Search

Trilobita

A Dictionary of Zoology | 1999 | | © A Dictionary of Zoology 1999, originally published by Oxford University Press 1999. (Hide copyright information) Copyright

Trilobita (trilobites; phylum Arthropoda) The most primitive arthropod class (or in some classifications a phylum, where the Arthropoda rank as a superphylum), known from more than 3900 fossil species. Inhabitants of Palaeozoic seas, the trilobites appeared first in the early Cambrian, had their widest distribution and greatest diversity in the Cambrian and Ordovician Periods, and became extinct in the Permian. The body was divided into three regions: an anterior cephalon, comprising at least five, fused segments; a mid-body (thorax), with a varying number of segments; and a hind region (pygidium). All three regions were divided by a pair of furrows running the length of the body, giving a trilobite appearance (i.e. a median or axial lobe, flanked on either side by a lateral lobe). The mouth was situated in the middle of the central surface of the cephalon. Paired gill-bearing limbs were attached to the membranous, pleural skeleton. X-ray studies show the eyes to have resembled the compound eyes of living arthropods. Trilobites ranged in size from 0.5 mm-long planktonic forms to those nearly 1 m in length; most species were 3–10 cm long.

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

  • MLA
  • Chicago
  • APA

MICHAEL ALLABY. "Trilobita." A Dictionary of Zoology. 1999. Encyclopedia.com. 28 Nov. 2009 <http://www.encyclopedia.com>.

MICHAEL ALLABY. "Trilobita." A Dictionary of Zoology. 1999. Encyclopedia.com. (November 28, 2009). http://www.encyclopedia.com/doc/1O8-Trilobita.html

MICHAEL ALLABY. "Trilobita." A Dictionary of Zoology. 1999. Retrieved November 28, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-Trilobita.html

Learn more about citation styles

Related newspaper, magazine, and trade journal articles from HighBeam Research

(Including press releases, facts, information, and biographies)

Historical Notes: The man in charge of the aqua company
Newspaper article from: The Independent - London; 11/6/1998; ; 700+ words ; SEXTUS JULIUS Frontinus was an extremely capable and versatile...towards the frontier on the Fosse Way. Frontinus carried out a large-scale campaign...for themselves. Domitian feared that Frontinus' successor in Britain, Julius Agricola...
Importance of making correct decisions part two: Methods to resolve faulty thinking
Magazine article from: Mining Engineering; 9/1/2003; ; 700+ words ; ...for further development," Julius Frontinus, highly respected engineer in Rome, 1st century A.D. Julius Frontinus seems to have fallen prone to the...estimates arc accurate judgements. Frontinus saw no new developments in his time...
Christianity was the first technologically driven religion
Newspaper article from: Charleston Gazette; 12/25/1998; ; 700+ words ; ...contemporary of Jesus, Sextus Julius Frontinus, wrote a book recounting his experience...gave the Romans potable water. Yet poor Frontinus was painfully aware that later generations...though famous, works of the Greeks," Frontinus almost pleaded with readers. Romans...
The new strategy of the indirect approach.
Magazine article from: Military Thought; 10/1/2006; ; 700+ words ; ...indirect approach (SIA). One of these predecessors was Frontinus, a Roman historian. In his work, Les Stratagemes, he reviewed...in the past that were known to him from historical works. Frontinus classified all of those military stratagems by the type of...
CHANGING TIMES
Newspaper article from: Sunday Star-Times; 1/14/2007; ; 700+ words ; ...learning - and eating - a decade from now. J ULIUS SEXTUS Frontinus stepped out of the time machine, typed his name into Google...dreamt of three decades ago. Yep. As a cannier analyst than Frontinus once said, the only constant is change itself. So how will...
Writings from the Workplace: Documents, Models, Cases.
Magazine article from: Technical Communication; 8/1/1996; ; 700+ words ; ...historical perspective afforded by this and other documents (such as Georgius Agricola's "De Re Metallica" and Sextus Julius Frontinus' "De Aquus") invites students to examine patterns and parallels in ancient and contemporary technical reports. Part 3...
Ancient & modern
Magazine article from: The Spectator; 5/20/2006; ; 562 words ; ...kept sewers permanently flushed. No wonder at the start of his treatise de Aquaeductu the superintendent of Roman aqueducts Frontinus ( AD 97) exclaimed, 'I ask you! Just compare with the vast monuments of this vital aqueduct network those useless Pyramids...
Standards past, present and future. (Standards in the 21st Century: a comprehensive review of standardisation is essential if it is survive).(Brief Article)
Magazine article from: Medical Device Technology; 5/1/2002; ; 700+ words ; ...survived in name or spirit, even if changing in value, for example, "libra "from which the British "pound" comes. 96 AD: Frontinus documented the customs and technology of aqueducts and compiled a catalogue of the standard dimensions of Roman pipes and...
Environmental biotechnology: theory and applications.(Book Review)
Magazine article from: Chemistry and Industry; 8/18/2003; ; 700+ words ; ...purifies water. The Romans, predictably, used technology to protect water resources. A Roman engineer, Sextus Julius Frontinus, in two books (AD 98) describes settling reservoirs and pebble catchers built into aquaducts. The first sand filter...
Sins and the Roman city; The historical adviser of next week's new bloodthirsty TV drama offers an A-Z of the sex, sacrifice and torture of everyday life in ancient Rome.
Newspaper article from: The Evening Standard (London, England); 10/28/2005; 700+ words ; Byline: JONATHAN STAMP A for AQUEDUCT "Greater than the Pyramids" was how the Roman writer Frontinus described the water system of ancient Rome, and it was all based on aqueducts that brought water into the city from as far as...

Related entries from encyclopedias, dictionaries, and thesauruses

Sextus Julius Frontinus
Encyclopedia entry from: Encyclopedia of World Biography Sextus Julius Frontinus The Roman magistrate, soldier, and engineer Sextus Julius Frontinus (ca. 35-ca. 104) is known primarily as a technical writer. Frontinus seems to have been of patrician descent, and his writings indicate that he...
Frontinus
Book article from: The Columbia Encyclopedia, Sixth Edition Frontinus (Sextus Julius Frontinus) , fl. AD 74, Roman administrator and writer. As governor...successfully done, that probably rendered possible the achievements of Frontinus' successor, Agricola . From his experience as curator aquarum...
Frontinus, Sextus Iulius
Book article from: The Oxford Companion to British History Frontinus, Sextus Iulius. Governor of Britain (73/4–77). Of unknown...campaigning against the Silures of south Wales, but otherwise passes over Frontinus' governorship in a sentence. Archaeology strongly suggests that he campaigned...
Frontinus, Sextus Julius
Book article from: A Dictionary of Architecture and Landscape Architecture Frontinus, Sextus Julius ( c. 35–105). Roman author of a major, clearly written, uncluttered treatise ( De Aquæ...
Balbus (Balbus Mensor[?])
Dictionary entry from: Complete Dictionary of Scientific Biography ...x201D; Other manuscripts name Frontinus — or even Fronto —...edition) its anonymous author credits Frontinus with a definition actually derived from...spurious, is believed to be the work of Frontinus; compare C. Thulin, “ Die...

Find thousands of answers for hundreds of subjects at Smart QandA .

All answers verified by trusted sources at Encyclopedia.com

Try Smart QandA now!

For students and teachers!

Encyclopedia.com provides students and teachers facts, information, and biographies from verified, citable sources, including:

Encyclopedia.com provides students and teachers facts, information, and biographies from verified, citable sources, including: