Defn: Having both a preoral and a posterior band of cilla; -- applied to the larvæ of certain annelids.
Defn: Situated in front of, or anterior to, the mouth; as, preoral bands.
The body is opaque, and encircled by five ciliary bands, and is without either mouth, anus or arms, and there is a tuft of cilia on the preoral lobe.
The mouth (4) is on the ventral surface at the junction of the preoral lobe with the hinder part of the body, and there is an anus (7) at the hind end.
In Asteroids the band of cilia becomes divided in such a way as to give rise to two bands, the one preoral, encircling the preoral lobe, and the other remaining postoral (fig.
The cilia of the preoral and postoral bands are not clearly differentiated at this stage.
At the anterior end of the preoral lobe is a nervous thickening of the ectoderm called the apical plate (1).
The antennae (second antennae) are of special interest on account of the clear evidence that, although preoral in position in all adult Crustacea, they were originally postoral appendages.
The epithelium of the outer surface was probably ciliated, and a portion of it in the preoral lobe differentiated as a sense-organ, with longer cilia and underlying nerve-centre, from which two nerves ran back below the ventral surface.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "preoral" in a variety of sentences. We hope that you will now be able to make sentences using this word.
