130 
Lapworth— Graptolites of Co. Down. 
The two preceding species are found in association at Tieveshilly. In 
Scotland the former appears to be restricted to the Riccarton Beds (Wenlock) ; 
and the latter occurs only in the Gala Group (Llandovery). 
19. Sp. 13. Monograptus M l Coyi. Lapw. Sp. nov. PI. 6, fig. 2. 
Polypary simple, monoprionidian, straight, several inches in length, and 
with an average width of one-sixth of an inch. Hydrothecae about 
30 to the inch, in contact throughout the whole of their extent, 
inclined at an angle of 45 0 ; of the general form of slender quad- 
rangular tubes, about five times longer than broad ; apertural margin 
convex, expanded into an oblique, blunt, triangular denticle. (Loc. 
Builth Bridge, Radnor.) 
The foregoing diagnosis has been drawn up from M‘Coy’s figure and 
description of a form from the Silurian Rocks of Wales (Palaeozoic Rocks and 
Fossils. PI. 1 B, fig 7, and p. 4) ( 1. ) which he erroneously identified with his 
Graptolithus lotus, originally founded upon a fragment of a Dichograptidian 
species, from the Skiddaw Slates of the Lake District (Quart. Journal Geol. 
Society, vol. 4, p, 223). Locality— A single well-preserved fragment only has 
been obtained from the Llandovery beds of Tieveshilly. 
20. Sp. 14. Monograptus Hisingeri. Carr. (See Geo. Mag., 1868. PI. 12, 
fig. 1.) 
(a ). Typical form. Locality — Tieveshilly. 
21. ( b ). Var. jaculum. Lapw. PI. 5, fig. 20. Localities— Coalpit 
Bay and Tullygarvan. 
22. Sp. 15. Monograptus cyphus. Lapw. PI. 5 > fig- 2 5 - Localities 
Coalpit Bay and Tullygarvan. 
23. Sp. 16. Monograptus leptotheca. Lapw, PI. 5 > ^ 2 * 22, Locality 
Some doubtful fragments only of this species have been collected from 
the black shales of Coalpit Bay. 
24. Sp. 17. Monograptus concinnus. Lapw. PI. 5 > ^ 2 * I 9 * Locality 
Coalpit Bay. 
(1.) Compare Rbmer in Leon and Bronn, Jahrbuch £ Min., 1855. p. 541. pLte 8, fig. 2. 
