I.–On some new Devonian Fossils

Abstract

In this specimen one valve (the left) and a part of the dorsal region of the other, remain visible; the rest of the right valve being bent down, broken, and imbedded in the matrix. This is a finely micaceous, non-calcareous, grey mudstone, weathering ferruginous towards one edge, which probably abutted on a crack open to water and atmosphere.The fossil, in the grey portion is darker than the matrix, and fairly represents the test of half of the carapace, with only a very thin lamina wanting, a broken edge of which is traceable (with a lens) near the ventral margin. This left valve measures 9·2 by 7·4 mm. It is subcircular, more boldly curved on the ventral than on the posterior margin, whilst the front margin is somewhat truncate, having a nearly straight edge from above downwards before it bends round into the ventral curve.

Notes on beyrichiacean ostracodes from the Early Devonian of NW Turkey andtheir palaeobiogeographical relations

“…Further material from the Early Devonian of the type area in the Rhenish Schiefergebirge of Germany: A second heteromorph internal mould was cited by Groos-Uffenorde (1982) from the slab SMF Mbg. 363 with 'Beyrichia roemeri Kays' figured by Kegel (1913) Jones and Woodward, 1889). These two slabs (part and counterpart of SMF Mbg.…”

“…As early as Kegel (1913) it was doubted that the figured Turkish specimens of Kayser were conspecific. Kegel's specimen from the Early Devonian of Germany (this internal mould, GPI MR 363, was deposited in the former collection of the GPI Marburg, refigured by Jordan 1964, and is now deposited in the collection of the Senckenberg Museum Frankfurt) is less elongate compared with the calcareous specimen of Kayser (1899) and all three narrow lobes are connected ventrally; it may belong to Zygobeyrichia devonica (Jones and Woodward, 1889) (see Z. subcylindrica).…”

“…Remarks: Because of the great variation in the distinctness of the lobation and the fact that only rare collections of external moulds show the tubercle on L 2 we use Zygobeyrichia subcylindrica [including Zygobeyrichia devonica (Jones and Woodward, 1889)] in a broad sense as mostly done.…”

“…Zygobeyrichia devonica (Jones and Woodward, 1889) is very closely related to, if not conspecific with, Z. subcylindrica.…”