DAVIDSON — SCOTTISH CARDONIFEEOUS BRACHIOPODA. 17 



Sp. hisulcata is one of the most abundant of our Scottish spirifers, the largest 

 example with which I am acquainted measuring eighteen lines in length by 

 twenty-eight in width and thirteen in depth. 



This shell has presented an extensive vertical range ; in Lanarksliire it is 

 found at Gare, at a depth of two hundred and thirty-nine fathoms below the 

 horizon of the "Ell coal;" at Raes Gill at three hundred and forty-three ; Lang- 

 shaw Burn three hundred and fifty-four ; Mosside three hundred and seventy- 

 three ; and at Braidwood Gill three hundred and ninety-seven fathoms. Ure 

 gives us a good figure of a specimen he had found at Lawrieston.* It has been 

 collected at Birkwood, near Lesmahago, and at Robroyston, to the north of 

 Glasgow. In Stii'lingshire it is not rare at Craigenglen, Balglass Burn, Mill 

 Burn, Gorrie Burn, and in the Campsie main limestone. In Dumbartonshire, at 

 Castlecary ; in Renfrewshire, at Barrhead, and Arden quarry, Thornliebank ; in 

 Ayrshire, at Roughwood, and West Broadstone, near Beith ; Auchenskeigli, 

 near Dairy; Craigie, near Kilmarnock; Monkredding and Goldcraig, near 

 Kilwmning ; and Neathernewtou, parish of Loudon, &c. It has also been ob- 

 tained from Arran and Bute. 



X. — Spirifera trigonalis. Martin. PL xii., figs. 16 — 18. 



Conchjliolithus anomifes trigonalis, Martin, Petrif. Derb. tab. 36, fig. I, 1809 ; 

 and Dav. Mon. Garb., p. 29, pi. v., fig. 28—33. 



In shape it is transversely trigonal, with its hinge-line as long, or slightly 

 shorter, than the greatest breadth of the shell ; the area is sub-parallel, and of 

 moderate width, the valves bemg almost equally deep ; the mesial fold is ele- 

 vated, angular, and often produced beyond the frontal margin of the lateral 

 portions of the valve; it is also more often divided by three principal ribs, of 

 wliich the central one is at tl\e same time the largest and most extended ; the 

 sinus is deep, and divided by from three to five longitudinal ribs, of which the 

 central one is also the most developed. Besides these, the surface of each 

 valve is ornamented with from fourteen to twenty -two simple ribs. 



This is also a common shell in Scotland, and does not appear to attain the 

 dimensions of Sp. hisulcata, with Avliich it has been sometimes confounded. Dr. 

 Fleming was certainly mistaken when, at p. 374 of his " History of British 

 Animals," he referred Ure's pi. xv., fig. 1, to the species under description. 



In Lanarkshire, Sp. tngonalis is found at three hundred and forty-three 

 fathoms below the " Ell coal" at Waygateshaw, and at Braidwood at three 

 hundred and seventy-five. It occurs also at Brockley, near Lesmahago; 

 at Moodies Burn, north-east of Glasgow, and in the main limestone near Camp- 

 sie ; and Renfrewsliire, at Arden quarry, near Thornliebank ; in Ayrshire, at 

 West Broadstone, near Beith ; Craigie, near Kihnamock ; and at Auchenskeigli, 

 near Dairy. In Midlothian, at Dryden, near Edinburgh ; and at Courland, 

 near Dalkeith. It has also been fomid in West Lothian and in Bute. 



XL — Spiripera pinguis. Sowerby. PL xii., fig. 28. 



Spirifera pinguis, Sow. Min. Con., vol. iii., p. 125, tab. 271, 1820 ; Spirifera 

 pinguis, Dav. Mon. Garb., p. 50, pL x., figs. 1—12. 



When full grown (under favourable circumstances) it is transversely oval, 

 but is also sometimes as wide as long, or even (though more rarely so) longer 

 than wide. The hinge-line is usually shorter than the greatest breadth of the 

 shell, the cardinal angles being rounded, and the area narrow. The dorsal 

 valve is not quite so deep nor so convex as the opposite ; the fold is moderately 



* It may be as well to mention that Mr. Bennie has ascertained that Lawrieston is the old 

 name for a place a few hundi-ed yards from the Capel Rig quarry, and now known by the 

 denomination of BrankamhaU, East Kilbride. 



VOL. III. C 



