436 MM. Jones and Kirkby — Carboniferous Ostracoda. 



an tero -ventral angle diagonally upwards, terminating abruptly, with 

 a downward bend, before reaching the posterior extremity ; another 

 long curved rib, commencing a little below the first, passes along 

 the ventral portion of the valve ; and occasionally another appears 

 not far from, and parallel with, the ventral fringe ; and near to the 

 antero-dorsal angle there is a short, curved rib, sharply pointed 

 behind. The free margin of each valve is ornamented with a radi- 

 ating fringe (and spines) similar in character to that of fimbriata. 

 The surface in Fig. 3 is granulated (var. granulata). Length, -o-Vinch. 



Good examples of this species have a granulated surface, but some 

 occur that are smooth (var. glabra, Figs. 1 & 2). In the latter state, 

 and particularly when the valves are rather worn, or flattened by 

 pressure, they simulate Kirhbya plicata, and are not always easy to 

 be distinguished from it. 



The ribs vary a little in development. The small one near the 

 antero-dorsal angle is often absent ; and that immediately below 

 occasionally extends across only the posterior half of the valve. 



This species is, as already stated, nearly allied to B. fimbriata; 

 but differs from it in its larger size, less elongated form, more 

 decided Beyrichian style of lobes, the granulated surface of its best 

 form, and the absence of the dorsal rib or crest of that species. 



Localities. — Calciferous-Sandstone series. Staneshiel Burn and 

 Tweeden Burn, Eoxburghshire. 



3. Beyrichiopsis cornuta, sp. nov. Plate XI. Fig. 11. 



From localities in the Carboniferous-limestone series (Lower) we 

 have a third fringed Beyrichia-like form. It is smaller than the 

 preceding species, has a spinose fringe all round the free margin, 

 possesses no ribs, but in their place has one or two large spines or 

 spikes projecting from each valve. Some of the specimens have 

 only a spine on the large posterior lobe or boss ; others have one on 

 the anterior lobe as well. The surface is smooth ; and the length is 

 from -gV to -gV inch. 



We name this form cornuta, and include it in Beyrichiopsis on 

 account of its fringe. 



It occurs at Linlithgow Bridge, Linlithgowshire ; Woodend Quarry, 

 Fifeshire ; and Dun Quarry, Lowick, Northumberland. 



4. Beyrichiopsis crinita, Jones and Kirkby. 



Beyrichia crinita, J. & K. 1884, Proc. Berwicksh. Club, vol. x. p. 322, pi. ii. 

 fig. 10, 11. 



This species was described by one of us (from specimens collected 

 by Mr. George Tate) in the Proceedings of the Berwickshire Nat. 

 Club, as above quoted. We have nothing to add to this, as no 

 additional specimens of it have been discovered. It is from the 

 Lower Carboniferous rocks of Alnwick Moor, Northumberland. 



Prof. Emmons notices and figures a fringed Beyrichian form from 

 the Trenton Limestone, of New York State, in his "Manual of 

 Geology," 2nd edit. I860, pp. 95 and 100. Probably this may belong 

 to our new genus. 



