PLATE XXXI. 

 Sub-genera Glyptograptus, Mesograptus, and Amplexograptus. 



FIGS. 



1 a — e. — Glyptograptus teretiusculus (Hisinger). (Page 250.) 



1 a. Characteristic specimen, well preserved. Wellfield, Builth. Llandeilo Beds. 



Lapworth's Collection. 

 1 b. Broader specimen, showing characteristic view of thecse. Pencerrig, near Builth. 



Landeilo Beds. Sedgwick Museum. 

 1 c. Exceptionally long specimen, sub-scalariform view. Builth Koad, Grwern-y-fed-fach. 



Llandeilo Beds. Eraser's Collection. 

 1 d. Specimen showing characteristic form. Ibid. 



1 e. Small specimen. Ibid. 



2 a — cl. — Glyptograptus teretiusculus, var. euglyphus (Lapworth). (Page 252.) 



2 a. Characteristic broad form. Cairn Eyan.Wigtown. Glenkiln Shales. Sedgwick Museum. 

 2 b. Long, narrow specimen, showing virgula, bi-profile view. Cross Burn at Ward, 



Barrhill. Glenkiln Shales. Geological Survey of Scotland. 

 2 c. Broad specimen, sub-scalai-iform view. Deugh Water, Knock ingarroch, Carsphairn. 

 Grlenkiln Shales. Geological Survey of Scotland. 



2 d. Long distal fragment, showing typical form. Birnock Water, Abiugton. Glenkiln 



Shales. Lapworth's Collection. 



3 a — d. — Glyptograptus teretiusculus, var. siccatus, Elles and Wood, nov. (Page 253.) 



3 a. Long distal fragment. Gwern-y-fed-fach, near Builth. Llandeilo Beds. Elles' 



Collection. 

 3 b. Complete small specimen, sub-scalariform view. On same slab as fig. 3 a. 

 3 c. Small distal fragment, sub-scalariform view. Gwern-y-fed-fach. Llandeilo Beds. 



Elles' Collection. 



3 d. Small specimen, bi-profile view. Ibid. 



4 a — d. — Glyptograptus dentatus (Brongniart). (Page 253.) 



4 a. Specimen figured, Lapworth, ' Quart. Journ. Geol. Soc.,' 1875, vol. xxxi, pi. xxxiv, 



fig. 5 c. Llanvirn Quarry. Lower Llanvirn Beds (zone of Didymog. bifidus). 



Sedgwick Museum. 

 4 b. Long specimen, preserved as an impression, showing characteristic appearance. 



Gilfach-wen, near Clynderwen Station. Upper Arenig Beds (zone of Didymog. 



bifidus). Geological Survey of England and Wales. 

 4 c. Small specimen, bi-profile view. Ukyd-y-behan Cottage, near Clyuderwen Station. Ibid. 

 4 d. Ditto. Cefin-faichen Farmyard, near Llanfallteg Station. Ibid. 

 5. — Glyptograptus dentatus, var. appendiculatus, Elles. (Page 255.) 



5. Type specimen. Figured, Elles, 'Quart. Journ. Geol. Soc.,' 1898, vol. liv, p. 518, fig. 30. 



Sedgwick Museum. 



6 a — c. — Glyptograptus sinuatus, Nicholson. (Page 255.) 



6 a. Complete and typical specimen, in relief. Cliff above Lower Bridge, Skelgill. Skelgill 



Beds. Sedgwick Museum. 

 6 b. Specimen in relief. Skelgill, Ambleside. Skelgill Beds. Sedgwick Museum. 



6 c. Typical specimen in Nicholson's original Collection. Skelgill, Ambleside. Skelgill 



Beds. British Museum (Natural History), S. Kensington. 



7 a — c. — Glyptograptus perscidptus, Salter. (Page 257.) 



la. Typical specimen in relief, obverse aspect. Gogofau, Carmarthen. Lower Llandovery. 

 Sedgwick Museum. 



7 b. Large specimen in partial relief. Ibid. British Museum (Natural History), 



S. Kensington. 



7 c. Compressed specimen. Ibid. Sedgwick Museum. 



8 a — -/. — Mesograptus foliaceus (Murchison). (Page 259.) 



8 a. One of the type specimens. Figured, Murchison, ' Silurian System,' 1839, pi. xxvi, 



fig. 3. Meadowtown, Shropshire. Llandeilo Flags. Geological Society of London. 

 8 b. Another figured specimen on same slab as fig. 8 a. 



8 c. Fairly complete specimen. Meadowtown. Llandeilo Flags. Lapworth's Collection. 

 8 d. Ditto. Geological Survey of England and Wales. 



8 e. Complete specimen in very low relief. Wooferton Mines, Shropshire. Whittery 



Shales (?). Lapworth's Collection. 

 8/. Specimen showing proximal end well preserved. Gwern-y-fed-fach, near Builth. 

 Llandeilo Beds. Fraser's Collection. 



9 a — d. — Mesograptus multidens, Elles and Wood, sp. nov. (Page 261.) 



9 a. Typical specimen, well preserved. Oak Wood, Pontesford, Shropshire. Lower Bala 



Beds. Lapworth's Collection. 

 9 b. Long specimen, somewhat narrower. Ibid. Benson's Collection. 

 9 c. Long, flattened specimen. St. Clears Bridge, S. Wales. Dicranograptus Shales. 



Elles' Collection. 

 9 d. Specimen with virgular tube prolonged distally. Ibid. 



