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ambulacrals, and it exhibits unique rows of<br />
spine-bearing dorsal arm ossicles. The genus<br />
Lapworthura Gregory was previously known<br />
only from the Ordovician of Scotland and the<br />
Silurian of England and Australia.<br />
2008010241<br />
澳 大 利 亚 mitrate 类 Victoriacystis 属 的 重<br />
新 描 述 兼 评 其 功 能 形 态 = Redescription of<br />
the Australian mitrate Victoriacystis with<br />
comments on its functional morphology. ( 英<br />
文 ). Ruta M. Alcheringa, 1997, 21(1/2): 81-<br />
101<br />
Re-examination of the type material, and<br />
study of new specimens of the Upper Silurian<br />
mitrate Victoriacystis wilkinsi Gill & Caster<br />
from the Heathcote area of Victoria, Australia,<br />
reveal additional details of its anatomy. Mitrates<br />
from the Lower Silurian of Hawthorn<br />
and the Lower Devonian of Kinglake West<br />
(Victoria Australia) are assigned to V. wilkinsi.<br />
New morphological features of Victoriacystis<br />
are: a sculptured median upper lip plate; five<br />
transverse rows of ventral plates; a complex<br />
ornament on the internal surface of the anteriormost<br />
ventral plates; a flexible articulation<br />
between dorsal and ventral fore-tail plates;<br />
and the presence of knobs on the ventral hindtail<br />
plates. Victoriacystis was probably a semiinfaunal<br />
animal which moved rearward within<br />
the sediment pulled by its tail. Yawing was<br />
reduced by the deep lateral head walls. The<br />
fore-tail could be flexed laterally to a large<br />
extent, whereas the hind-tail could proably<br />
also act as a lever. Spines might have helped<br />
the animal to rest on sediment, to increase<br />
stability in water currents, and/or to bring food<br />
particles in suspension.<br />
2008010242<br />
不 列 颠 群 岛 兰 多 维 列 世 ( 早 志 留 世 ) 新 的<br />
海 百 合 类 动 物 ( 棘 皮 动 物 ) = New Crinoids<br />
(Echinodermata) from the Llandovery (Lower<br />
Silurian) of the British Isles. ( 英 文 ). Fearnhead<br />
F E; Donovan S K. Palaeontology, 2007,<br />
50(4): 905-915<br />
British Llandovery crinoids remain poorly<br />
known. Three species are documented herein<br />
that were originally described, but not published,<br />
by W. H. C. Ramsbottom. Clematocrinus<br />
ramsbottomi Fearnhead sp. nov. (Tortworth<br />
Inlier, Gloucestershire; Telychian) has a<br />
heteromorphic column, N434243414342434,<br />
radices directed away from the crown, and ten<br />
long, uniserial arms with a pustular aboral<br />
sculpture and long, slender pinnules. Clematocrinus<br />
spp. are widely distributed in the Silurian<br />
of England. Ptychocrinus mullochillensis<br />
Fearnhead and Donovan sp. nov. (Girvan<br />
district, Strathclyde; Rhuddanian) is the second<br />
report of this Upper Ordovician–Lower<br />
Silurian genus from outside North America.<br />
Although incompletely known, this species is<br />
distinguished by its hidden infrabasals, 20<br />
arms and sunken interbrachial plates with a<br />
strongly stellate sculpture. Petalocrinus bifidus<br />
(Bather MS) Donovan and Fearnhead sp.<br />
nov. (Woolhope Inlier, Herefordshire; Telychian)<br />
is locally common enough to give its<br />
name to a mappable lithostratigraphic unit, the<br />
Petalocrinus Limestone. Unlike other Petalocrinus<br />
species known from the Silurian of<br />
China, northern Europe and North America,<br />
the fused arms of P. bifidus are divided in two<br />
by a proximal adoral ridge and an associated<br />
distal notch. Unlike extant crinoids, Petalocrinus<br />
probably lived as a rheophobe; the fused<br />
arms may have acted to deter predators.<br />
2008010243<br />
苏 格 兰 St Andrews 密 西 西 比 亚 纪 维 宪 期<br />
Asbian 分 支 海 百 合 一 新 属 后 肠 软 组 织 的 保<br />
存 = Soft-tissue preservation of the hind gut in<br />
a new genus of cladid crinoid from the Mississippian<br />
(Visean, Asbian) at St Andrews, Scotland.<br />
( 英 文 ). Kammer T W; Ausich W I. Palaeontology,<br />
2007, 50(4): 951-959<br />
Soft-tissue preservation of the hind gut, or<br />
anal sac, in the tegmen of Tubulusocrinus (gen.<br />
nov.) doliolus (Wright) from the Mississippian<br />
(Visean, Asbian) Pittenweem Formation at St<br />
Andrews, Scotland, is the first of its kind<br />
known in crinoids; it sheds important new<br />
light on the nature of the cladid tegmen. Many<br />
cladid crinoids had a calcite-plated anal sac<br />
that may have functioned like a chimney to<br />
prevent fouling of the ambulacra. The tubular,<br />
uncalcified anal sac of Tubulusocrinus may<br />
have functioned like a hose by pointing down<br />
current between the arms to avoid fouling of<br />
the ambulacra. Its smaller size may also have<br />
required less energy to produce than a heavyplated<br />
sac. The hind gut is apparently preserved<br />
by haematite replacement, which was<br />
probably altered from original authigenic pyrite<br />
that formed soon after catastrophic burial.<br />
2008010244<br />
英 格 兰 和 威 尔 士 密 西 西 比 亚 纪 杜 内 期<br />
Ivorian 分 支 海 百 合 和 可 曲 海 百 合 = New<br />
cladid and flexible crinoids from the Missis-<br />
65
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