﻿248 R. Etheridge, Jun. — Contributions to British Pakeontology. 



character of the latter ; distance between the apex and the lower 

 margin is much reduced ; the spire has a tendency to become hori- 

 zontally coiled instead of vertically. The aperture is eloDgately 

 oval. 



Ohs. — The relation of the variety to the typical form is seen in 

 the pronounced inrolled spire, feebly sinuated sharp edges to the 

 aperture, with an elongated little-marked lobe in front, and the fine 

 concentric striee, with at intervals a stronger lamina of growth. 



The horizontal manner in which the spire is coiled appears to be 

 a peculiar character of this variety. Were it compressed laterally 

 instead of from above downwards, it would be more closely allied to 

 Capuliis (Fileopsis) compressa, Goldf., from the Eifel, as figured by 

 Quenstedt.' 



Loc. and Horizon. — Magazine Limeworks (quarry at), near Path- 

 head, Haddingtonshire, in shale above No. 2 Limestone (L. Carbon- 

 iferous Limestone Group). The figured specimen was obtained by, 

 and is in the Cabinet of Mr. J. Simpson, Edinburgh, to whom I am 

 indebted for calling my attention to it, and after whom I name the 

 variety. Specimens are also in the Coll. Geol. Society of Scotland, 

 collected by Mr. J. Bennie. 



Genus Dentalium, Linnaeus. 

 Dentalium inornatum, M'Coy? Plate XIL Fig. 1. 



D. inornatum, McCoj, 1844 ; Synopsis Carb. Foss. Ireland, p. 47, t. 5, f. 30. 

 „ „ Tennant, 1847 ; Strat. List Brit. Foss., p. 105. 



„ „ D'Orbigny, 1849 ; Prodrome de Pal., i. p. 127. 



„ „ Morris, 1854 ; Cat. Brit. Foss., 2nd ed.. p. 246. 



„ „ Pictet, 1855 ; Traite de Paleontol., vol. iii. p. 303. 



Sp. Chars. — Shell slightly curved, very gradually tapering; mouth 

 circular. Surface smooth, without ornamentation (M'Coy). 



(Jbs. — Omitting the question of dissimilarity in size, the only 

 appreciable difference between the specimen and M'Coy's figure is 

 the rate at which they respectively taper. Of the descriptions of 

 smooth Palaeozoic DentaUi with which I am acquainted, 1). inornatum 

 appears to be allied to D. granosum, var. Icevigatum, Eichwald,'* and 

 more especially in minute delicacy to the Permian B. Speyeri, 

 Geinitz.^ A comparison may also be instituted with D. venustum, 

 Meek and Worthen ; * but the latter is a less curved form, and tapers 

 less rapidly. The shelly matter is exceedingly well preserved in our 

 specimen, and not a trace of any ornamentation is to be seen. In 

 the larger of Prof. M'Coy's figures there is a notch or slit in the 

 margin; but as nothing is said about this in the description of the 

 species, I presume it is accidental. 



Loc. and Horizon. — " Ardross Limestone," shore (high-water 

 mark) immediately east of Ardross Castle, near Elie, Fife (see 

 remarks under Orthoceras Brownianum). 



1 Handbucb, 1852, t. 35, f. 11. 



2 Lethsea Rossica, 1860, i. p. 1062. 



3 Dyas, 1861, p. 57, t. 12, f. 11-13. 



•» Illinois Geol. Report, Palaeontology, vol. iii. 1866, p. 284, t. 19, f. 8. 



