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Duodecimedusina palmeri sp. nov. is described from the Upper Llanflovery of the Malverns and West Midlands. This extends the stratigraphic range of the genus previously described from the Carboniferous and Lower Devonian. It is also the first record from Europe.

• Read more about A new medusoid (?) from the Silurian of England

Macrocystella mariae Callaway 1877, type species of Macrocystella, has a stem which is divisible into proximal and distal portions; a theca composed of 4 basal, 5 infra-lateral, 5 lateral, 6 radial, and some oral plates; a large periproct surrounded by 5 thecal plates; biserial unbranched brachioles grouped into 5 ambulacra and arising from the margins of the flattened oral surface. In all these respects it agrees with Mimocystites bohemicus Barrande 1887, type species of Mimocystites which becomes a subjective junior synonym of Macrocystella.

• Read more about Macrocystella Callaway, the earliest glyptocystitid cystoid

Morphological features, growth, mode of life, and stratigraphical distribution are examined in more than 300 extremely well-preserved specimens of Discohelix from the Sicilian Lower and Middle Jurassic. In some species parabolic ribs similar to those in ammonites are formed owing to resorbtion during brief discontinuities in growth. Deviated peristomes recurring at an angle of more or less 72° and resulting in a pentagonal outline of the shell, are developed in two species for which the new subgenus Pentagonodiscus (type species D.(P.) angusta n. sp.) is established.

• Read more about Discohelix (Archaeogastropoda, Euomphalacea) as an index fossil in the Tethyan Jurassic

Pedicellariae have been discovered on the Silurian (Ludlovian) echinoids Echinocystites pomum and Palaeodiscus ferox from Leintwardine, England. All pedicellariae of both species are tridentate in form and simple in morphology. Most are interambulacral in position. Pedicellariae of E. pomum are abundant, all are probably three-valved, and of variable size. Those of P. ferox are relatively rare, apparently two-valved, and small in size. These pedicellariae, and an Australian occurrence, are the oldest known echinoid pedicellariae.

• Read more about Pedicellariae of two Silurian echinoids from western England

Seven species and two subspecies belonging to four genera of ammonoids (Clymeniina and Goniati-tina) are described from a Famennian horizon, Platyclymenia Zone, a few hundred feet below the erosive base of the Carboniferous in the vicinity of Keepit Dam, near Tamworth, New South Wales. Three new species of Clymeniina are described: Genuclymenia keepitensis, Platyclymenia (Platyclymenia) teicherti, and P. (P.) alterna.

• Read more about Famennian ammonoids from New South Wales

Species of Aquilapollenites Rouse emend. Funkhouser are present in the interbasaltic lignites of Shiaba and Bremanoir, Mull, Scotland. The bearing of this on the age of the lignites is discussed; it is believed that this may be pre-Eocene.

• Read more about Aquilapollenites in the British Isles

Chubbina jamaicensis gen. et. sp. nov. and Chubbina macgillavryi spt nov, from the Cretaceous rocks of Jamaica and southern Mexico are described. Borelis cardenasensis Barker and Grimsdale is placed in the new genus. Chubbina appears to be a useful index for the Upper Cretaceous (Upper Campanian to Maastrich-tian) of the Greater Antilles and Central America.

• Read more about Chubbina, a new Cretaceous alveolinid genus from Jamaica and Mexico

The cuticle of four species of the genus Dicroidium is described. The material has been found in close association with Rhexoxylon stems in the locality of Ischigualasto, San Juan Province, Argentina. Two new combinations are proposed: Dicroidium zuberi (Szajnocha) and Dicroidium elongatum (Carruthers). It is proposed that Dicroidium leaves are related to Rhexoxylon stems (a) because they are associated in four Triassic localities of South Africa and Argentina, and (b) because there is a structural relation of both organs with the Palaeozoic pteridosperms.

• Read more about Studies on Triassic fossil plants from Argentina. IV. The leaf genus Dicroidium and its possible relation to Rhexoxylon stems

A new Ordovician edrioblastoid, Astrocystites distans sp. nov., and other miscellaneous pelmatozoan plates are described from the lower part of the Cliefden Caves Limestone WNW. of Mandurama, New South Wales. The edrioblastoid is similar to the only other species of Astrocystites known, A. ottawaensis Whiteaves from the Trenton Limestone of Ottawa, which was hitherto the sole representative of the group. This represents the first record of an edrioblastoid outside North America. Sections of the Australian material have revealed details of internal structures not previously known in the group.

• Read more about Astrocystites distans sp. nov., an edrioblastoid from the Ordovician of eastern Australia

The colour markings in Phacops rana and Greenops boothi are described and discussed. It is suggested that P. rana had the ability to change its pigmentation. Only four examples of colour markings in trilobites have been mentioned in the literature.

• Read more about Colour markings in Phacops and Greenops from the Devonian of New York