Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/481

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3. On some Bivalve Entomostraca, chiefly Cyprinidae;, of the Carboniferous Formations. By Prof. T. Rupert Jones, F.R.S., F.G.S.

(This paper has been withdrawn by permission of the Council.)

[Abstract.]

Bivalved Entomostraca are abundant in many shales and limestones throughout the Carboniferous formations ; in the lists published in the ' Transactions of the Geological Society of Glasgow' (vol. ii. 1867, and vol. iii. suppl. 1871) upwards of 50 species are enumerated as known in the coal-fields of Western Scotland alone. Other species have since been recognized in that and other localities. Some of the larger forms of Ostracoda are not rare in the Carboniferous Limestone of Belgium and the British Islands; and, indeed, in some instances they are so plentiful as to constitute masses or bands of limestone, as at Longnor (Derbyshire), Bolland (Yorkshire), Bathgate (Scotland), Poolvash (Isle of Man), Caldy Island (South Wales), Kildare (Ireland), &c. Here and there in the Coal-shales some large forms, especially Cypridinoe, also occur.

Many years ^go some of these larger Ostracods were figured and described by Professors J. Phillips (1836), M'Coy (1839), and De Koninck (1841), and their Entomostracal relationship pointed out. The collections made by M. J. Bosquet, F.C.G.S., in Belgium, Mr. Joseph Wright, F.G.S., at Cork, Ireland, Mr. J. H. Burrow, M.A., at Settle, Yorkshire, Mr. Young, Glasgow, Mr. Grossart, Salsburgh, Dr. Rankin, Carluke, and others, and submitted to the author and his friend Mr. J. W. Kirkby, have elucidated many obscure points in the history of these old Entomostraca. Numerous other specimens from Ireland, Scotland, Yorkshire, Derbyshire, and the Isle of Man, communicated by friends, have also been studied ; and the results will be given in detail in a Monograph by Messrs. Jones and Kirkby, to be published by the Paleeontographical Society, and now in the press. The main points of geological interest arrived at are as follows : —

The Entomoconchus of M'Coy proves to have the Cypridinal character of anterior sinus and gape, as intimated by Messrs. Jones and Kirkby in 1863 (Rept. Brit. Assoc' for 1863, Tr. Sect. p. 80) ; and besides E. Scouleri, M'Coy, which is found in Belgium, Yorkshire, and Ireland, together with a variety ovalis (Ireland), two other species have now been determined, E. orbicularis (Cork, Ireland) and E. globosus (Beith, Scotland), thanks to the researches of Mr. Joseph Wright, F.G.S., of Belfast, and Mr. John Young, of Glasgow, respectively, all from the Mountain Limestone.

A closely allied genus Offa* is also indicated, in which the sinus and gape are very slightly pronounced, in a carapace otherwise somewhat resembling the foregoing. Only one species, 0. Barrandiana (Cork, Ireland), is as yet known.

M'Coy's " Daphnia primoeva " belongs to Cypridina proper

  • Offa, a pellet.