SUPPLEMENT.— CYLICOCERAS. xlix 



Date of Existence. — Bradford ensis, or Murchisonse hemera. 



In the neighbourhood of Crewkerne there are several other species more or less 

 allied to the last, and they seem to be somewhat peculiar to that district. Their 

 preservation is too often inferior. 



X. Genus — Asthenoceras, 1 S. Buckman. 



(Type — Asthenoceras nannodes, S. Buckman.) 



Definition. — Stenoleptogyral, latumbilicate ; laterally flexiradiate ; peripherally 

 anguliradiate, subfastigate, alti-septicarinate. 



Distinction, — The thin whorls associated with a wide umbi- 



Fig.G. — Radial line 



licus and a septicarina distinguish this genus from any one of Asthenoceras 



. . nannodes, 



described m this Supplement. 



Remarks. — The strong carination and the curvature of the radius may suggest 

 affinity with An coliocera s; but the wide umbilicus and the paucity of ornament 

 forbid direct connection with Anc, cariniferum. 



1. Asthenoceras nannodes, S. Buckman. Plate XXXIII, figs. 13 — 16; Suppl., 



Plate XI, fig. 28. 



1890. Gtiiammoceras nannodes, This Monogr., PI. xxxiii, figs. 13 — 1G. 



Remarks. — The radial curve is depicted in fig. 6 above, and also in Suppl., 

 PL XI, fig. 28. 



Date of Existence. — Murchisonse hemera. 



XI. Genus — Cylicoceras, S. Bucltman. 



(Type — Cylicoceras undatum, sp. n.) 



Definition. — Platy- subpachygyral, subangustumbilicate, laterally 

 subflexiradiate, peripherally obtusanguliradiate, subfastigate, non- 

 septi-carinate. 



Distinction. — From Lioreras, radial line — the peripheral projection 

 is shorter : mode of growth — thicker in proportion to umbilicatioUj Fl1 



line of 



tlicocera 



undatum. 



'Aadet'i'is, without strength, feeble. 



periphery less acutely fastigate. 



o 



