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Tricolpopollianthus burejensis gen. et sp. nov., the staminate heads with tricolpate grains in situ, are described from the Upper Cretaceous of the Amur Basin, Far East of the U.S.S.R.

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Isograptus Moberg is one of the most diverse, abundant, and stratigraphically useful graptolite genera in Australasia. It first appears in the Chewtonian stage (mid Arenigian), dominates the faunas of the following Castlemainian and Yapeenian stages, and becomes extinct by the end of the Darriwilian (Late Llanvirn or Llandeilo).The genus Isograptus is diagnosed and is distinguished by its proximal symmetry, apparently unique among reclined didymograptids; the sicula and theca I1 form a symmetrical pair such that the axis of rhabdosome symmetry passes between them.

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Analysis of extensive palynologic data from the English Wealden (Early Cretaceous) has enabled a comprehensive set of 17 palynologic assemblage-types to be defined in detail. This has been done in such a way that a rapid preliminary survey of a preparation will enable it to be placed in one of the assemblage-types so that its value for stratigraphic correlation or palaeoecology can be predicted without long and possibly uneconomic use of observation time. With the exception of Celyphus rallus gen. and sp. nov.

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The remains of three nymphal Palaeodictyoptera from the English Coal Measures (Upper Carboniferous) are described: Rochdaliaparkeri Woodward 1913; Idoptilus onisciformis n. gen., n. sp.; and a wing pad and prothoracic fragment situated in the pelvis of the holotype of the amphibian Eugyrinus wildi. The two named nymphs are onisciform, with prothoracic and true abdominal paranotal lobes, and posterolaterally directed wing pads; they show no aquatic adaptions; and the relief of their pronota is complex, and comparable with that of the meso- and metanota.

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Despite mineralogical alteration Triassic ammonoids provide significant data the layers forming the shell wall and umbilical plug. Two layers (outer and inner test) are recognized in the outer wall. Outer test incorporates growth lines, ornament and colour markings, defines the fundamental architecture, was evidently secreted only on the flanks and venter, probably only at the mantle edge. Inner test deposits are secondary, modifying in various ways the chamber interior, and were secreted both dorsally and ventrally, probably at the mantle surface.

• Read more about Observations on the shell structure of Triassic ammonoids

A description is given of the types of gymnospermous wood occurring in material collected from the Kimmeridgian of the East Sutherland coast. These types are compared with those collected from the Sandringham Sands of Norfolk. All of the material is described in terms ofbiorecords and events: references are made to previously described species in the form of comparison records. In traditional taxonomy some of the specimens are referable to Cedroxylon Kraus and the remainder to Pityoxylon Kraus.

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The brachiopod Aratanea monodi Schmidt 1967 from Mauretania (West Africa) is put into the synonomy of Clarkeia antisiensis, chief constituent of the Malvinokaffric Clarkeia fauna of Central South America of Silurian age. The recently described fauna of latest Ordovician age from South Africa is considered to have been the ancestor of the Clarkeia fauna. In particular Marklandella africana is reassigned to Heteror-thella, and considered the ancestor of Heterorthella freitana; Plectothyrella haughtoni is considered the ancestor of Clarkeia itself.

• Read more about The origin of the Silurian Clarkeia shelly fauna of South America, and its extension to West Africa

Of 4,000 specimens of fossil decapods collected from three stratigraphically different localities in the Pierre Shale (Upper Cretaceous, Maestrichtian) of South Dakota, twenty specimens of the brachyuran Dakoticancer overanus Rathbun were found preserved in Sailer's position. Several of these specimens have the portion of the carapace which lies outside pleural sutures still attached to the sternal plastron, proof that they are exuviae. The part of the carapace between the pleural sutures is completely overturned on each specimen and rotated on most specimens.

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A new species of the dasycladacean alga Trinocladus is described as T. exoticus sp. nov.; it comes from the Upper Cretaceous of Borneo. Other Trinocladus spp. are Cretaceous and Eocene of the circum-Mediterranean, Middle East, and Caribbean.

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Monograptids recorded and described from Arctic Canada for the first time comprise Monograptus cf. cornutus (Urbanek), M. cf. balticus Teller and M. helicoides sp. nov. from probable late Ludlovian; M. bouceki Pribyl and Saetograptus pilosus sp. nov. from mid-Pridolian; M. uniformis angustidens Pribyl and M. uniformis parangustidens subsp. nov. from the latest Pridolian angustidens Zone; M. aequabilis aequabilis (Pribyl) and M. cf. hercynicus subhercynicus Willefert from the lower Lochkovian uniformis Zone; and M. aequabilis notoaequdbttis Jaeger and M. cf. craigensis Jaeger from the Pragian.

• Read more about Monograptids from the Upper Silurian and Lower Devonian of Yukon Territory, Canada