SANGUINOLITES VARIABILIS. 379 



Gurdy, near Beith ; Garngad Road, Glasgow ; Roscobie ; Woodend, Fordel, and 

 Charleston, Queensferry, Fife. 



Observations. — This species was described by M'Coy under the genus 

 Leptodomus {op. cit.). This was a genus established by him in 1841' to receive a 

 shell now referred to Protoschizodus fragilis (see above, p. 250). Later, in 1855, 

 this genus was amended by M'Coy in such a way that it could include neither of 

 its original species {op. cit., p. 277). I am of opinion that the genus as amended 

 is not a good one, and that the shells referred to it do not form a natural group, 

 and can be placed in other well-defined genera. 



Sanguinolites costellatns differs in no generic details from the 8. variabilis 

 " ovate variety," described and figured by M'Coy at the same time. The latter 

 is less strongly curved from above downwards, less convex, and has a narrower, 

 less convex dorsal slope, larger concentric ribs on the shell, and much smaller 

 umbones. Both these species agree in every generic detail with the shell that 

 M'Coy takes as the type of his genus Sanguinolites {8. angustatus). 



8. costellatus seems to have a much more local distribution than 8. variabilis. 

 As far as I can ascertain at present, it is only found in the Lower Carboniferous 

 Limestone series of Scotland, but is found at this horizon both in the east and 

 west of Scotland. When the railway was made from Giffen to Kilbirnie, in the 

 cutting at Gurdy, near Beith, numerous well-preserved specimens were found in 

 a bed of shale, generally correlated with the limestones of Kerrsland Glen, which 

 form the upper part of the Lower Limestone series of Scotland. 



In 18-i4 M'Coy described a fragment of a shell as Sangiiinolites costellatus, but 

 this shell turns out to be the posterior end of an internal cast of 8olenom/ija 

 costellatus. 



Sanguinolites variabilis, M^Goij, 185L Plate XLIV, figs. 1, 3 — 8. 



San&uinolites variabilis (par.-), M'Coy, 1851. Aun. Mag. Nat. Hist., 2nd ser., 



vol. vii, p. 174. 

 — Morris, 1854. Cat. Brit. Foss., 2nd edit., p. 223. 



~ — il/' Co.y, 1855. Brit. Pal. Foss., p. 508, pi. 3 F, figs. 6,7. 



? — — Youn(^ and Armsirong {\)&T»),1S7\. Trans. Geol. Soc. 



Glasgow, vol. iii, Supplement, p. 54. 

 ? — ' — Armstrong, Young, and Robertson (pars), 1876. Cat. 



West. Scottish Foss., p. 55. 

 -, — — JBigshi/ (^urs), 1877. Thes. Devonico-Carbonif., p. 313. 



— — Ethcridge (pars), 1888. Brit. Foss., pt. 1, Pal., p. 290. 



Specific Characters. — Shell subquadrate, gibbose, regularly convex, only slightly 

 compressed posteriorly, inequilateral. The anterior end is short, deep, and 



