20 
THE GEOLOGIST. 
the Sp. tmguiculus, Pliillips, from the Devonian series, are only synonyms of tlic 
present species, and to wliicli must iilso be added the Sp. Gohlfiissiaiia of Prof, 
de Koniuek. It docs not appear to have often exceeded about four lines in 
length by four and a-half ui width and two in dej)th, but is usually a much 
smaller sliell, at least so in Scotland. Sp. Urii is certainly the most abundant 
of Scottish s]^)irifcrs, and may be picked up by thousands in several localities, 
such as at Hill Head, in Lanarkshii-e, where it occurs at three hundred and 
fifty-six fathoms below the " Ell coal," and three hundred and seventy-five at 
KUeadzow. It is foimd plentifully on the east bank of the Avon, near Strath- 
avou ; and at Coalburn, near Lesmahago. Li Stirlingshire it has been found in 
three dilFercnt stages, viz., the Craigeuglen beds, under the maia-limestoue, and 
in the black-limestone and shale of South Hill, Campsic. 
XVI. Spibifeea lineata. Martm. PI. xii., fig. 31. 
Conchiliolithus anomites Uneatm, Martin, Petrif. Derb., tab., xxxvi., fig. 3, 
1809 ; and Dav. Mon. Carb., p. 62, pl. xui., figs. 1—13. 
In shape tliis shell is either transversely oval or sub-orbicular, the hinge-line 
being much sliorter than the width of the shell, and the cardinal angles 
rounded ; the beaks are incurved and more or less approximate, the area small. 
Ventral valve evenly convex, and rarely possessing any mesial elevation, or fold, 
while the dorsal valve is rather deeper than the opposite one, and either 
uniformly convex, or presenting a shallow longitudinal depression, which 
bccoiues most apparent towards the front. Externally the surface was covered 
\vith numerous eonecntric ridges, rarely in any place more than a line apart, 
but usually very much closer, and from each of which departed numerous con- 
tiguous closely packed spiues, which thus formed a series of rows, or fringes 
over the shell. When the spines are absent, which is the general condition in 
which the shell is foimd, the surface apjiears marked by numerous and regularly 
imbricated lines, the radiating ones being produced by the small elevations from 
which each spine took its birth, as I have attempted to show in the enlarged 
representation, fig. Z\c, and which is very different from the irregular manner 
in which the spines are scattered over the surface of Sp. Urii, of which fig. 30e. 
is an enlarged illustration. Sp. lineata is a common sliell in the carboniferous 
limestone and slialcs of Scotland ; but none of the examples I have yet seen 
attained the dunensions presented by some which occur both hi England and 
Ireland. 
At Gare in Lanarkshire Sp. lineata occurs at two hundred and thirty-nine 
fathoms lower than the " Ell co;il ;" at Braidwood, three hmidred and forty- 
three ; at Harestanes, three hundi'cd and seventy-five ; and at NcMeld, four 
hundred and ten. It may also be collected at Brocklcy, and Middlcholm near 
Lesmahago. In Ayrshire it occurs at Roughwood, and West Broadstone near 
Beith ; HaUerhh-st, Stevenston ; and Craigie near Kilmarnock. In Renfrew- 
shire, at Barrhead ; and at Arden and Orchard quarries near Thornliebank. 
In Dumbartonshire, at Castlecary. In Stirlingshire, under the main limestone 
and in the Calmy limestone or Balquarhage beds, Campsie, as well as at Corric 
Burn. In Mid Lothian it is not rare at Drydeu, near Edinburgh ; and at 
Courland, near Dalkeith. Dr. Eleming mentions Dreghorn and Ayr, and it 
was also found in Arran by Prof. Ramsay. 
Sub-genus Spiriferina. D'Orbigny. 1847. 
The species located in this sub-genus differ from Spirifera (which they re- 
scmlile in external sliape) by the perforations or canals which traverse their 
shells, as well as by the development, of a large elevated mesial septum ui the 
interior of the ventral valve, to the sides of which was attached the adductor, 
or occlusor muscle. 
