The Lower Carboniferous blastoid Astrocrinus tetragonus Austin and Austin from Grassington, Yorkshire, and the validity of Astrocrinus benniei Etheridge

2021 ◽  
pp. pygs2021-001
Author(s):  
C. R. C. Paul ◽  
D. B. Macurda ◽  
J. J. Savill
Keyword(s):  
Basal Plate ◽  
Basal Surface ◽  
Lower Carboniferous ◽  
Rare Exception ◽  
First Time ◽  
Carboniferous Limestone

Despite surviving longer than any other blastozoans, blastoids were exceptionally conservative in their morphology and usually symmetrically pentaradiate. Astrocrinus is a rare exception that lacked a stem and some thecal plates, although differing interpretations of its morphology and taxonomy have been published. Astrocrinus had a flattened, tetralobate theca covered in minute spines, and with a plane of symmetry through the AB interray and the D ray. Four ambulacra are long, thin, and curved down deep sinuses between the thecal lobes to reach the basal surface. The D ambulacrum is short, broad and horizontal. Astrocrinus tetragonus was first described from the Carboniferous Limestone of Settle, Yorkshire. Here it is recorded for the first time from the Brigantian, near Grassington. The new specimens confirm that A. tetragonus had a single basal plate which is kite- shaped, entirely surrounded by four radials and separated from the D ray radial. Astrocrinus benniei was described from the Scottish Brigantian and its basal plate is elongate pentagonal with a short common suture with the D ray radial. Astrocrinus occurs in the Irish Asbian and Brigantian. To date, only A. tetragonus can be confirmed from Ireland.

V.—On the Shell-Structure of Chonetes Laguessiana, De Kon

1883 ◽  
Vol 10 (8) ◽  
pp. 368-371
Author(s):  
John Young
Keyword(s):  
Shell Structure ◽  
The Other ◽  
Lower Carboniferous ◽  
Carboniferous Limestone

The specimens selected for illustration of the shell-structure of this species of Chonetes were found in a bed of shale in the Lower Carboniferous Limestone series at Capelrig old quarry, in the parish of East Kilbride, Lanarkshire. The fossils in this shale have their structure generally well preserved, there being less change, through crystallization of the lime present in the shells of the various organisms, than is found in those obtained from most of the other fossiliferous localities in Western Scotland.

The inadunate crinoid genus Cryphiocrinus Kirk

1977 ◽  
Vol 114 (3) ◽  
pp. 209-214 ◽  
Author(s):  
Harrell L. Strimple
Keyword(s):  
West Virginia ◽  
Type Species ◽  
Lower Carboniferous ◽  
First Time

SummaryCryphiocrinus Kirk is a genus which may possess a delicate stem, or may lose the stem as an adult, making it essentially eleutherozoic. C. girtyi Kirk, type species, is documented with certainty from Chesterian rocks of Oklahoma and Arkansas for the first time. C. rotundus Kirk is reported from the Renault Formation of Illinois and a possible occurrence in the Pride Mountain Formation of Alabama is noted. The genus has previously been recognized in Chesterian, Upper Mississippian, (Lower Carboniferous), strata exposed in West Virginia, Kentucky and Oklahoma, U.S.A. Possible affinity with Hosieocrinus Wright from the Lower Limestone Group (Visean) in Scotland is discussed.

A review of Silvanerpeton miripedes, a stem amniote from the Lower Carboniferous of East Kirkton, West Lothian, Scotland

2006 ◽  
Vol 97 (1) ◽  
pp. 31-63 ◽  
Author(s):  
Marcello Ruta ◽  
Jennifer A. Clack
Keyword(s):  
Cladistic Analysis ◽  
Lower Carboniferous ◽  
Total Group ◽  
Skull Roof ◽  
Lower Jaw ◽  
First Time ◽  
Basal Position

ABSTRACTPreviously described and new specimens of the anthracosaur Silvanerpeton miripedes from the Scottish Viséan of East Kirkton yield important new data which allow us to provide a more complete reconstruction of the skull roof, palate, braincase and lower jaw. A stout sacral rib and an incompletely ossified tarsus with a subquadrangular intermedium are also recorded for the first time. A remarkably well preserved humerus in extensor view shows similarities with humeri of immature specimens of the embolomere Proterogyrinus. A new cladistic analysis, built from combining characters used in two recent matrices, places Silvanerpeton in a basal position relative to embolomeres and more derived stem amniotes. Data from Silvanerpeton inform character polarity near the base of the amniote total group. We discuss some morphofunctional implications of character changes at the root of total group amniotes, acquisition of terrestrial habits, and patterns of early disparity in this clade.

scholarly journals IV.—On a New Species or Discites (Discites Hibernicus) from the Lower Carboniferous Limestone of Ireland

1893 ◽  
Vol 10 (6) ◽  
pp. 251-254
Author(s):  
Arthur H. Foord ◽  
G. C. Crick
Keyword(s):  
New Species ◽  
The Other ◽  
Present Communication ◽  
Lower Carboniferous ◽  
The Subject ◽  
Carboniferous Limestone ◽  
A New Species

The specimen which forms the subject of the present communication was obtained by one of the writers from the Carboniferous Limestone, near Dublin. Although one side of the specimen is covered by matrix, yet the other side and the periphery are so splendidly preserved, and the shell has not been distorted during fossilisation, that the characters of the fossil can be accurately determined (see Woodcut, p. 254).

A Collection of Carboniferous Limestone Fossils in the Skipton Museum

1941 ◽  
Vol 78 (3) ◽  
pp. 220-223
Author(s):  
G. Bond
Keyword(s):  
Large Collection ◽  
Lower Carboniferous ◽  
Working Through ◽  
Carboniferous Limestone

Recently I have had the opportunity of working through a large collection of Lower Carboniferous fossils, of which there appears to be no record in geological literature. The collection was made by R. H. Tiddeman from the district between Pateley Bridge and Settle, and is now in the care of the Skipton Museum. The bulk of the collection was probably made between 1890 and 1900 and has hardly been touched since.

scholarly journals New views about the Sizim suite (Lower Permian, the Polar Urals)

2019 ◽  
Vol 489 (1) ◽  
pp. 53-56
Author(s):  
N. S. Inkina
Keyword(s):  
Deep Sea ◽  
Western Slope ◽  
Lower Permian ◽  
Polar Urals ◽  
North East ◽  
The North ◽  
Composition And Structure ◽  
First Time ◽  
Carboniferous Limestone ◽  
The Polar Urals

The article for the first time presents data on the material composition and structure of the Sezym Formation of the Lower Permian of the Western slope of the Polar Urals, which lies with stratigraphic disagreement on shallow medium-Carboniferous limestone and according to the overlapping deep-sea Artinian terrigenous deposits. New data are important for paleogeography and geodynamic reconstruction of the North-East of the European platform in the late Paleozoic.

scholarly journals GOLD-JASPEROID MINERALIZATION IN ZONE OF THE SHARTYMSKIY FAULT (SOUTH URALS)

2020 ◽  
Vol 19 (3) ◽  
pp. 275-281
Author(s):  
P. V. Kazakov ◽  
Keyword(s):  
Southern Urals ◽  
South Urals ◽  
Weathering Crust ◽  
The Southern Urals ◽  
Lower Carboniferous ◽  
Stage Of Development ◽  
Deposit Type ◽  
Economic Concentration ◽  
Carboniferous Limestone ◽  
Gold Bearing

The Shartymskiy Graben was formed at zone of the Shartymskiy Fault in the late collision stage of development of the Southern Urals on the joint of the Western and Eastern Magnitogorsk sub-zone in conditions of variable compression and stretching, and was made with the Lower Carboniferous limestone. Occurrences of gold-bearing metasomatites (jasperoids, sericite-chlorite-carbonate-quartz, sericite-quartz) have been established in the precontact zones of carbonates, gabbro-dolerites, diorites dykes, and small intrusions of sub-alkaline leuсograniteporphirs of the Shartymskiy massif. Mediated connection with them of gold sprouts is established. The gold economic concentration of the Vorontsovskiy deposit type is expected on the certain sections of metasomatites of jasperoid association and their weathering crust.

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