PLATE XXXIV. 



Subgenera Thysanograptus, Nymphograptus, Neurograptus, Gladiograptus, 

 Plegmatograptus, and Gothograptus ; and Genus Retiograptus. 



Figs. 



1 a — d. — Thysanograptus Harknessi (Nicholson). (Page 325.) 



1 a. Typical specimen with incomplete lacinia. Hartfell. Hartfell Shales. British 

 Museum (Natural History). Specimen labelled by Nicholson. (? Type.) 



1 b. Broader form -with more complete lacinia. Hartfell. Hartfell Shales (zone of 

 Climacog. Wilsoni). Geological Survey of Scotland, Edinburgh. 



1 c. Sub-scalariform view, on same slab as fig. 1 b. 



1 d. Broad specimen, with incomplete lacinia. Hartfell. Hartfell Shales (zone of 



Climacog. Wilsoni). Geological Survey of Scotland, Edinburgh. 



2 a — d. — Thysanograptus HarJcnessi, var. costatus (Lapworth). (Page 327.) 



2 a. Typical specimen. Cog Burn, a few yards above junction with Polroisk, Dumfriesshire. 



Glenkilu Shales. Geological Survey of Scotland, Edinburgh. 

 2 b. Type specimen, with well-developed lacinia, figured Lapworth, " Grapt. Co. Down," 



' Proc. Belfast Nat. Field Club,' pi. vi, fig. 26. Dobb's Linn. Hartfell Shales (zone 



of Climacog. Wilsoni), Lapworth's Collection. 

 2 c. Specimen in very low relief. Oakwood, Pontesford, Shropshire. Llandeilo-Bala. 



Benson's Collection. 



2 d. Specimen with incomplete lacinia. Dobb's Linn. Hartfell Shales. Lapworth's 



Collection. 



3 a — c. — Thysanograptus retusus (Lapworth). (Page 328.) 



3 a. Type specimen, figured Lapworth, 'Ann. Mag. Nat. Hist.' [5], vol. v, pi. v, figs. 24 a — d. 



Llandrindod Wells. Llandeilo. Lapworth's Collection. 

 3 b. Specimen showing virgula, doubtfully referable to this species. Hartfell Spa ? 

 Glenkilu Shales ? Lapworth's Collection. 



3 c. Broad specimen with virgula. Cwm Brith Bank, near Llandrindod Wells. Upper 



Arenig. Collection Miss C. Chamberlain. 



4 a, b. — Nymphograptus velatus, Elles and Wood, nov. (Page 329.) 



4 a. Two specimens in association, with well-developed lacinia. Ettrick Bridge End, 



Selkirk. Hartfell Shales (zone of Dicellog. anceps). Geological Survey of Scotland, 

 Edinburgh. 



4 b. Smaller fragment, with less perfect lacinia, profile view. Ibid. 



5 a — c. —Neurograptus fibratus (Lapworth). (Page 831.) 



5 or. Type specimen, bi-profile view, ? figured Lapworth, 'Cat. West. Scott. Foss.,' pi. iii, 



fig. 62. Dobb's Linn. Hartfell Shales. Lapworth's Collection. 

 5 b. Beverse of 5 a. Ibid. 



5 c. Specimen in scalariform view, showing scopulate processes. Ibid. 



6 a — e. — Neurograptus margaritatus (Lapworth). (Page 332.) 



6 a. Typical specimen, with almost complete lacinia. Dobb's Linn. Hartfell Shales 



(zone of Dicranog. Clingani). Lapworth's Collection. 

 6 b. Similar specimen with less perfect lacinia. Ibid. 

 6 c. Specimen in scalariform view, on same slab as 6 a. 

 6 d. Larger specimen, with incomplete lacinia. Hartfell Spa. Hartfell Shales. Wood's 



Collection. 



6 e. Distal fragment on same slab as 6 d. 



7 a — d. — Retiograptus Geinitzianus, Hall. (Page 316.) 



7 a. — Specimen in low relief. Benan Burn, river Stinchar, Girvan. Glenkilu Shales. 



Geological Survey of Scotland, Edinburgh. 

 7 b. Larger specimen, compressed. Birnock Water. Glenkiln Shales. Lapworth's 



Collection. 

 7 c. Proximal fragment. Ibid. 



7 d. Part of ventral lattice. Ibid. 



8 a — d. — Gladiograptus Geinitzianus (Barrande). (Page 336.) 



8 a. Well-preserved specimen in low relief, reverse aspect. Burn, Nether Stennis Water, 



6^ miles N.N.W. of Langholm. Riccarton Beds. Geological Survey of Scotland, 



Edinburgh. 

 8 b. Compressed specimen, showing reticula, obverse aspect. Pull Beck. Browgill Beds 



(zone of Monog. crispus). Sedgwick Museum (Coll. Marr). 

 8 c. Smaller specimen from same locality as 8 a. 

 8 d. Somewhat narrow specimen. Grieston Quarry, Innerleithen. Upper Gala Beds. 



Lapworth's Collection. 



