REMOPLEURIDES BARRANDEI. 31 



axial segments and three pairs of pleura?. It corresponds closely with the genus 

 Apatohephalus, which has lately been separated by Brogger from DilcellocephahbS? 

 A species of Apatohephalus has recently been described by the author from the 

 Llandeilo beds of co. Waterford. 2 The British species at present attributed to 

 Dikellocephalus show too many pleurae on the lateral lobes, but the Canadian 

 species T>. (Apato.) magnificus, Billings, 3 agrees in only having three pairs. Of the 

 European forms, the Swedish Apato. sermtus, Angelin, 1 which occurs associated 

 with the genus Triarthrus, as at Girvan, is apparently the nearest ally; and the 

 examples figured by Holm (op. cit.) show r the closest approach to the Balclatchie 

 form. In the number of axial rings D. (Apato.?) microphthalmia, Linnar., 5 has a 

 close agreement. Recently Wiman 6 has created a new genus Uobergia for the 

 reception of the last mentioned species, and his figure of the pygidium much 

 resembles our Girvan specimens ; but the axis is less clearly defined, less pointed, 

 and provided with fewer rings. Wiman, moreover, associates this pygidium with 

 head-shields bearing a considerable resemblance to Uemopleurides barrandei. But 

 it hardly seems advisable without further evidence to adopt his conclusions and 

 attribute to Bemo. barrandei the pygidium here assigned to Apatohephalus, though 

 both occur at Balclatchie. 



Collections. — Mrs. Gray (f. M.) ; Museum of Practical Geology. 



Horizon and Locality. — Balclatchie Group (Llandeilo) : Balclatchie. 



Genus REMOPLEURIDES, Portlock. 

 1. Remopleurides barrandei, Nicholson and Etheridge, 1879. Plate V, figs. 1 — 4. 



1879. Remopleurides barrandei, Nicholson and Etheridge, e.p., Mon. Silnr. Foss. Girvan, fasc. ii. 

 p. 151, pi. x, fig. 13 (non figs. 14, 15, 16, nee pi. xi, fig. 16). 

 ? 1879. Remopleurides, sp. ind (b), Nicholson and Etheridge, ibid., p. 150, pi. x, fig. 12. 

 1899. Remopleurides barrandei, e.p., Mem. Geol. Surv., Silur. Rocks Brit., vol. i, Scotland, pp. 509, 

 514, 673. 



1 Brogger, "TJeb. Verbreit. Euloma-Niobe Fauna,' 7 'Nvt. Mag. f. Naturvidensk.,' vol. xxxv, 1896, 

 p. 1 79. 



2 Reed, 'Quart. Journ. Geol. Soc.,' vol. lv, 1899, p. 758, pi. xlix. figs. 14 —16 ( Tramoria punctata) ; 

 and ' Geol. Mag.,' dec. iv, vol. viii, 1900, p. 46. 



3 Billings, ' Pakeoz. Foss. Canada,' vol. 1 (1865), p. 399, fig. 376. 



p Angelin, 'Pal. Scand.,' p. 88, pi. xli, fig. 10; Brogger, 'Die Silur. Et. ii ami iii," p. 126, pi. iii, 

 figs. 7—8; Holm, ' Sver. Geol. Undersold!,' ser. G\ No. 176, p. 18, pi. i, figs. 3—5 (1898). 



- 1 Linnarsson, 'Geol. Fciren. Forhandl,' vol. ii, 1875, p. 494, pi. xxii, fig. 3 ; Holm (op. cit.), -pi. i, 

 fig. 2. 



fi Wiman, " Palaont, Notiz. No. 3," 'Bull, Geol. Instit. Upsala,' No. 11, vol. vi, |.(. 1 (1902), 

 p. 77, pi. v, fig. 4. 



