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In both families the skeleton consists of little rosettes of calcite crystals grouped round a central axis. In the Discoasteraceae the crystals are arranged each with its optic axis parallel with the principal (= central) axis; the individual crystals have a bilateral symmetry with virtual suppression of the trigonal symmetry characteristic of inorganically grown crystals.

• Read more about Crystal development in Discoasteraceae and Braarudosphaeraceae (planktonic algae)

An ontogenetic series of Z. leckenbyi has been obtained from a locality in the mid-Cotswolds. Serial sectioning has enabled determination of the microstructure and development regime of the loop. The work reveals that a loop of adult character is formed by the time the brachial valve is about 4-0 mm long, confirming Elliott's suspicion that in zeilleriids the early stages of loop development were passed through very quickly. During early development phases the loop is connected to a septal pillar rising from the floor of the brachial valve.

• Read more about The development of the loop in the Jurassic brachiopod Zeilleria leckenbyi

The type specimen of Inocemmus tenuis Mantell displays probable tooth impressions of Ptychodus on the ventral margin of the left valve. The predation is interpreted, and the general problem of vertebrate predation on Inoceramidae, which were the dominant Cretaceous bivalves, is discussed.

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Ammonites from the transgressive Cretaceous at Millheim-Broich near Essen in Germany are from the Zone of Hypoturrilites carcitanensis, at the base of the Cenomanian.

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Marcouia, gen. nov. has large palmately compound leaves in which the pinnae are deeply divided into linear, lateral segments. The segments (pinnules ?) contain broad midribs and parallel veins that often divide and anastomose one or more times before reaching the margins. Leaves from the Chinle Formation that were formerly referred to as Ctenis are here assigned to Marcouia. Marcouia is not classified and is known only from the lower part of the Upper Triassic Chinle Formation in eastern Arizona and western New Mexico.

• Read more about Marcouia, gen. nov., a problematical plant from the Late Triassic of the southwestern U.S.A.

The Saltern Cove Goniatite Bed, which contains upper Frasnian conodonts, ostracods, and gonia-tites, is shown also to contain blocks of Famennian limestone and to lie within a sequence of Famennian sediments. From the sedimentology, it is considered that Famennian limestone clasts were reworked into Frasnian muds which were then transported en bloc into Famennian sediments. A Schwellen area (rise) nearby is suggested by the nature of the derived limestone blocks.

• Read more about The Upper Devonian Saltern Cove Goniatite Bed is an intraformational slump

Muscle scars are described in Salpingostoma buelli (Whitfield 1878) and Tremanotus alpheus Hall 1865 with reference to finely preserved specimens of Bellerophon spp. The taxon Salpingostomatidae Koken 1925 is abandoned with transferal of Salpingostoma Roemer 1876 to the subfamily Bucaniinae of the Bellerophontidae. A new subfamily of the Sinuitidae, the Tremanotinae, is proposed to accommodate Tremanotus Hall 1865 and Boiotremus Horny 1962. Brief discussion is given of described species of the three genera from the Silurian of North America.

• Read more about Observations on some lower Palaeozoic tremanotiform Bellerophontacea (Gastropoda) from North America

Idiohamites ellipticoides Spath is an aberrant species of the genus Idiohamites which shows the recoiling trend so widespread in Cretaceous heteromorph ammonites. Its ornament is identical with some members of the largely southern hemisphere family Labeceratidae, but study of suture lines show this to be merely a case of homeomorphy. The species is described and illustrated on the basis of large new collections.

• Read more about The affinities of Idiohamites ellipticoides Spath (Cretaceous Ammonoidea)

Shell structural and morphological studies of Cadomella and various species of the Spiriferida and Chonetacea show that Cadomella belongs to the Koninckinacea within the Spiriferida. The term supra-apical is considered inappropriate for the pedicle foramen of the Koninckinacea. The relationship between pseudo-punctae and tubercles is discussed.

• Read more about The systematic position of the Jurassic brachiopod Cadomella

Two specimens of the ammonite genus Texanites from the Santonian sediments of False Bay, Zululand, have aptychi, identified as Spinaptychus spinosus (Cox), in their body chambers. This association appears to be a valid one, and is compatible with previous records of Spinaptychus from Texanites-beatiag strata in England, North Africa, the Middle East, and North America, although no previous associations have been described.

• Read more about A Texanites–Spinaptychus association from the Upper Cretaceous of Zululand