138 



PROF. T. E. JOKES OK KUMMULITES ELEGANS 



figs. 10, 10 a-c. At p. 146 they properly refer to Sowerby's fig. 3 

 as N. variolaria, and figure it in pi. ix. fig. 13. 



1854. In Morris's Catal. Brit. Foss. 2nd edit. p. 38, N. elegans, 

 Sow., is placed under Nummulites planulatus, Lam. 



1862. The Eev. 0. Fisher, in his Memoir " On the Bracklesham 

 Beds," Quart. Journ. Geol. Soc. vol. xviii., allocates Nummulites 

 vao'iolarius, losvigatus, and Prestwichianus to their several beds of the 

 Bracklesham and Barton formations, at pages 67, 70-84, and says 

 (p. 84) : — " At Alum Bay the greater part of the fossiliferous beds in- 

 cluded in No. 29 of Mr. Prestwich's Section (Quart. Journ. Geol. Soc. 

 vol. ii. pi. 9) may be correlated satisfactorily with those usually known 

 as the Barton and Highcliff: series. There is a well-known and marked 

 seam of dark green sand} r clay, containing abundance of Nummulina 

 Prestivichiana. It contains Barton forms ; and therefore we may 

 safely carry the Barton series down so far, though it is lower in 

 series than any bed from which fossils have hitherto been collected 

 at Highcliff. The same jSummulite-bed occurs there also " (see 

 p. 87). 



1862. At Whitecliff Bay part of the < No. 17 ' of Prof. Prestwich's 

 section, Quart. Journ. Geol. Soc. vol. ii. p. 254, and of the xix. 

 of Mr. 0. Fisher's section, Q. J. G. S. vol. xviii. pp. 69 & 70, is 

 regarded by Mr. Fisher as the equivalent of the green bands which 

 form the base of the Barton beds at Highcliff and Alum Bay, and 

 these contain the Nummvlina jplanulatus [wemmelensis], var. Prest- 

 ivichiana. 



1862. Quart. Journ. Geol. Soc. vol. xviii. pp. 93, 94. Appendix 

 B to the Rev. 0. Fisher's memoir " On the Bracklesham Beds." 



" Note on Nummttlika plaktjlata, Lamarck, sp., var. Peest- 

 wichiaka, Jones. By T. Rupert Jones, F.G.S. 



" This little Nummulite is discoidal, smooth, and flat, rarely in 

 any degree biconvex, even in the young state, unless the outer whorl 

 has been flattened by pressure ; about -j^-th inch in diameter, and 

 yVth in thickness. The gently sigmoid and semitranslucent edges 

 of the septa appear at the surface, and but seldom rise above it 

 (except when the specimens are mechanically compressed, which is 

 a common condition). The whorls (three [four] in large specimens) 

 are all visible in empty shells made transparent by water or Canada- 

 balsam; they are proportionally wide for Nummvlina (the outer 

 whorl making half [|th or -|th] the width of the disk). The chambers 

 are about half as long as wide, neatly curved, but subject to ii-regu- 

 larity of growth. The lateral portions of the chambers, though very 

 shallow, are continued over the surface towards the centre on each 

 face, and are rather straighter in old specimens than in the young [?]. 



" This neat and delicate variety of Nummulina planulata, Lamarck, 

 sp., has long been known in a clay containing much green sand, at 

 Alum Bay, Isle of "Wight (lower part of the bed ' No. 29 5 of Mr. 

 Prestwich's Section, Quart. Journ. Geol. Soc. vol. ii. p. 257, pi. 9. 

 fig. 1) ; but it has not hitherto been described*. It is near to MM. 



* The writer did not then know that Mr. J. De C. Sowerby had included this 

 iXummulite under the description of N. elegans in the Min. Conch, vol. vi. p. 76. 



