prostomium

American  

[proh-stoh-mee-uhm] / proʊˈstoʊ mi əm /

noun

prostomia plural

1. the unsegmented, preoral portion of the head of certain lower invertebrates.

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prostomium British  

/ prəʊˈstəʊmɪəm /

noun

1. the lobe at the head end of earthworms and other annelids: bears tentacles, palps, etc, or forms part of a sucker or proboscis

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Other Word Forms

Derived Forms

• prostomial
  adjective

Inflected Forms

Nouns

• prostomia
  plural

Etymology

Origin of prostomium

1865–70; < New Latin < Greek prostómion mouth. See pro- ², stoma, -ium

Example Sentences

See Examples For:

prostomium

The setae are implanted metamerically in accordance with the metamerism of the body, which consists of a prostomium followed by a number of segments.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 7 "Cerargyrite" to "Charing Cross" by Various

In any case the cavity of the prostomium is single, and not formed, as is the cavity of the segments of the body, by paired coelomic chambers.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 7 "Cerargyrite" to "Charing Cross" by Various

The peculiar prostomium of Tomopteris is described below.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 7 "Cerargyrite" to "Charing Cross" by Various

The parapodia of Chaetopoda are never coated with dense chitin, and are, therefore, never converted into jaws; the primitive “head-lobe” or prostomium persists, and frequently carries eyes and sensory tentacles.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 6 "Armour Plates" to "Arundel, Earls of" by Various

The prostomium has many long filaments which recall the gills of the Sabellids, &c.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 7 "Cerargyrite" to "Charing Cross" by Various