rostellum

American  

[ro-stel-uhm] / rɒˈstɛl əm /

noun

plural

rostella

1. Biology. any small, beaklike process.

2. Botany. a beaklike modification of the stigma in many orchids.

3. Zoology.

   1. a projecting part of the scolex in certain tapeworms.

   2. a part of the mouth in many insects, designed for sucking.

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rostellum British  

/ rɒˈstɛləm /

noun

1. biology a small beaklike process, such as the hooked projection from the top of the head in tapeworms or the outgrowth from the stigma of an orchid

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Other Word Forms

• rostellate adjective

Etymology

Origin of rostellum

1750–60; < New Latin; Latin: little beak, snout, diminutive of rōstrum snout ( see rostrum); for formation, see castellum

Example Sentences

It is to discover whether rostellum yet retains some of its primordial function of being penetrated by pollen-tubes.

From More Letters of Charles Darwin — Volume 2 by Darwin, Francis, Sir

I did think it possible or probable that perfect fertilisation might have been effected through rostellum.

From More Letters of Charles Darwin — Volume 2 by Darwin, Francis, Sir

I will say nothing about the rostellum, stigmatic utriculi, fertility of Acropera and Catasetum, for I am completely bewildered: it will rest with you to settle these points by your excellent observations and experiments.

From More Letters of Charles Darwin — Volume 2 by Darwin, Francis, Sir

I have asked Asa Gray for seeds, to whom I have mentioned your observations on rostellum, and asked him to look closer to the case of Gymnadenia.

From More Letters of Charles Darwin — Volume 2 by Darwin, Francis, Sir

Asa Gray's observations on the rostellum of Gymnadenia are very imperfect, yet worth looking at.

From More Letters of Charles Darwin — Volume 2 by Darwin, Francis, Sir