On the Radiolaria in the Devonian Rocks of New South Wales

Abstract

On the invitation of the authors of the foregoing paper, I very willingly consented to undertake an examination and description of the radiolaria occurring in the extensive series of Devonian rocks in New South Wales which they have recently brought to light, and accordingly they forwarded to me, in the spring of 1897, a box of hand-specimens of typical examples of the different kinds of radiolarian rocks, and these have been supplemented since by a few other specimens received during the present year. Microscopic sections have been prepared from them; and from such as contained the radiolaria in good preservation (as, for example, the dark siliceous limestones and some of the volcanic tuffs from Tamworth), numerous slides were made, so as to obtain as large a variety of the organisms as possible. The rocks sent me were derived from the following four localities:—(1) Bingara and (2) Barraba: red jaspery cherts; (3) Jenolan Caves and vicinity: black chert; (4) Tamworth: black chert, dark siliceous limestone, siliceous claystone or shale, and volcanic tuff. II. C haracter of the R ocks and M ode of P reservation of the R adiolaria Before describing the radiolaria, it will be desirable to refer to the character of the rocks of which they form so important a parb, and to their mode and condition of preservation. ( a ) The Chert-rocks with Radiolaria. The jaspery cherts of Bingara and Barraba are hard and flinty, of a brick-red tint, and fairly translucent in section. They are traversed in all directions by thin microscopic veins