{ _Seminula_ } Viseen }
Avonian { } } Dinantien
{ { _Syringothyris_ } }
{ Clevedonian { }
{ { _Zaphrentis_ } Tournaisien }
{ { _Cleistopora_ } }

The upper Avonian (Kidwellian) is well developed about Kidwelly in
Carmarthenshire. The lower substage (Clevedonian) is well displayed near
Clevedon in Somerset.

See A. Vaughan, "The Carboniferous Limestone Series (Avonian) of the Avon
Gorge," _Proc. Bristol Naturalists' Soc._, 4th series, vol. i. pt. 2, 1906,
pp. 74-168 (many plates); and T. F. Sibley, "On the Carboniferous Limestone
(Avonian) of the Mendip area (Somerset)," _Q.J.G.S._ vol. lxii., 1906, pp.
324-380 (plates).

(J. A. H.)

AVONMORE, BARRY YELVERTON, 1ST VISCOUNT (1736-1805), Irish judge, was born
in 1736. He was the eldest son of Frank Yelverton of Blackwater, Co. Cork.
Educated at Trinity College, Dublin, he was for some years an assistant
master under Andrew Buck in the Hibernian Academy. In 1761 he married Miss
Mary Nugent, a lady of some fortune, and was then enabled to read for the
bar. He was called in 1764, his success was rapid, and he took silk eight
years afterwards. He sat in the Irish parliament as member successively for
the boroughs of Donegal and Carrickfergus, becoming attorney-general in
1782, but was elevated to the bench as chief baron of the exchequer in
1783. He was created (Irish) Baron Avonmore in 1795, and in 1800 (Irish)
viscount. Among his colleagues at the Irish bar Yelverton was a popular and
charming companion. Of insignificant appearance, he owed his early
successes to his remarkable eloquence, which made a great impression on his
contemporaries; as a judge, he was inclined to take the view of the
advocate rather than that of the impartial lawyer. He gave his support to
Grattan and the Whigs during the greater part of his parliamentary career,
but in his latter days became identified with the court party and voted for
the union, for which his viscounty was a reward. He had three sons and one
daughter, and the title has descended in the family.

AVRANCHES, a town of north-western France, capital of an arrondissement in
the department of Manche, 87 m. S. of Cherbourg on the Western railway.
Pop. (1906) 7186. It stands on a wooded hill, its botanical gardens
commanding a