402 CARBONIFEROUS LAMELLIBRANCHIATA. 



Localities. — Bng'land : the Redesdale Ironstone Shales, Northumberland. 

 Scotland: Skolie Burn, at Addiebrown Hill, Blackburn; Knockhill Quarry, 

 Strathkiness, St. Andrews. Ireland : Lower Limestone Shale, Newton and 

 Drumline, co. Clare. 



Observations. — This species is founded on two specimens from Skolie Burn, a 

 large number of specimens from Strathkiness, in the collection of the Geological 

 Survey of Scotland, and a single specimen from the Lower Limestone Series 

 of Ireland. It is characterised by its narrow transverse form, its comparatively 

 long, narrow, and projecting anterior end, the fine concentric markings of the 

 surface, and the absence of radiating lines on the dorsal slope. 



The slab from Strathkiness shows casts of the interior as well as of the 

 exterior, so that all the important anatomical details have been made out. 



All the above specimens were at first identified as 8. iransversus, Portlock, 

 sp., but I have shown above, at page 389, that this shell is identical with 

 8. pUcatus ; and this species does not possess an angular oblique ridge, and the 

 ribs and sulci of the surface-markings are much more pronounced. 



I think that this is probably the shell referred to 8. plicatus by Mr. Kirkby 

 {op. cit.), as very fine drawings of the shell occur in his MS. book of figures of 

 fossils from the Calciferous Sandstone series of Fife. 



SANGUiN'oiiiTES LUXDRiANS, de Kouinclc, 1885. Plate XL VI, figs. 3 — 5. 



? Sanguinolakia gibbosa, Sow., 1829. Min. Conch., vol. vi, p. 92, pi. dxlviii, 



fig. 3. 

 Sakguinolites luxueians, f/e A'o?iZHc^% 1885. Aed. Mus. Eoy. Hist. Nat. Belg., 



vol. xi, p. 73, pi. xvi, figs. 1 — 3. 



Specific Characters. — Shell above the medium size, transversely suboval, 

 obliquely gibbose, very inequilateral. The anterior end is short, narrowed from 

 above downwards, its border elliptically rounded, the lower limb of the curve 

 passing rapidly downwards into the inferior margin, which is feebly convex, and 

 apparently almost subparallel with the dorsal border. Posteriorly the lower 

 margin curves upwards to form a rounded acute angle with the posterior border, 

 which projects much beyond the rest of the valve. The posterior border is very 

 obliquely truncate from above downwards and backwards, and shortened by the 

 approach of the upper and lower margins ; it forms a well-marked obtuse ano-le 

 with the upper border. The latter is arched, produced, and elevated behind, 

 much shorter than the lower margin. The umbones are tumid, incurved, and 

 twisted forwards, contiguous, only slightly elevated, excavated in front by a large, 

 deep, and elongate lunule, and situated in the anterior fifth of the valve. A more 



