﻿BRITISH FOSSIL CEPHALOPODA. 115 



Our species is often confounded with 0. bullatum, but it is immediately distinguished 

 by its ornaments being much larger, and never appearing as impressed si rise. 



Distribution. — A small specimen, whose maximum diameter is four lines, is in 

 Dr. Grindrod's collection as from the Woolhope Shale. It abounds, however, chiefly 

 in the Lower Ludlow of Ledbury (1), Leintwardine (5), and Dudley (1). It occurs 

 also in the Upper Ludlow of Ludlow (3) and of Kirby Moor (1), and in the Upper 

 Silurian of Kerry. 



It is recorded by authors as from Lower Silurian rocks in Ireland, but I have 

 little doubt that the shells intended belong to 0. lineatum. Thus M'Coy records it 

 from the schist of Tullyconnor, co. G-alway, and Baily from Lower Silurian, Fairy- 

 mount. The same explanation may probably be given, in some cases certainly, to 

 the following references : viz., M'Coy's to the Upper Bala, Coldwell, Bala Shale, 

 Builth, and Bala Limestone, Ooniston ; Hackness and Nicholson from Randy Pike ; 

 and in the Catalogue of Scottish Fossils from Drummuck. Salter, however, records 

 the species also from the Lower Ludlow of Coalbrookdale. 



Orthoceras pimbriatum, Sowerby, PI. YIII. figs. 1, 2, 3. 



1838. Orthoceras fimbriatum, Sowerby in Murchison's ' Silurian System,' pi. 13, fig. 20, 



p. 632. 

 1854. „ annulatum, var. fimbriatum, Salter in Murchison's ' Siluria,' pi. 26, 



figs. 1, 2, p. 232. 

 1868. „ „ Barrande, ' Syst. Silur. de Boheme,' pi. 291, fig. 7. 



1873. „ ,, var. fimbriatum, Salter, ' Camb. and Silur. Fossils,' p. 158 ; 



also same page includes 0. Brightii. 

 Syn. 1838. Orthoceras Brightii, Sowerby in Murchison's ' Silurian Syst.' pi. 12, fig. 21, p. 626. 

 1848. „ „ (part.) N>-t 0. mocktreense, Phillips, 'Mem. Geol. Surv.' 



vol. ii. pt. i. p. 353. 



1852. „ „ M'Coy, ' Pal. Fossils,' p. 313. 



1853. Actinoceras Brightii, Morris, ' Catalogue of Brit. Foss.' p. 289. 



1854. Ormoceras Brightii, Salter in 'Siluria,' pi. 27, fig. 5. 



Type. — I have not been able to discover the type of this species, but the figure 

 and description are really sufficient. The section is nearly circular, and the- rate of 

 increase is 1 in 10. The ornaments are, first, longitudinal narrow convexities, 

 somewhat less than a line in breadth, and separated by re-entering angles ; and 

 secondly, a number of raised laminae passing directly across the shell, about a line 

 apart, usually about the same size, but larger ones occasionally occur at irregular 

 intervals : these laminae are thrown into festoons, so that the parts concave towards 

 the aperture lie on the convexities. The septa are direct, and have a convexity of 

 •£ the diameter; their distance, however, is not shown, but they are said to be 

 moderately numerous. The siphuncle is central, and \ of the whole diameter in 

 size. Greatest diameter, 2 inches. From the Lower Ludlow rock. 



Q 2 



