EXPLANATION OF THE PLATES. , 23 
PLATE IX. 
FOSSILS OF THE LLANDEILO ROCKS, 
HYDROZOA or POLYZOA.—GRAPTOLITIDZ. 
Fic 1.—a,b, c. GRAPTOLITHUS SAGITTARIUS, Linneus. 
Hisinger, Leth. Suec,, pl. xxv., fig. 6, Monograpsus sagittarius, Prof. Geinitz, 
Die Graptolithen (1852), pl. 1x., fig. 3 
G. incisus.—Harkness, Journ. Geol. Soc., vol. vii., p. 6, pl. i, fig. 8 ; 
Memoirs Geological Survey, vol. iii., p. 329, pl. xi. a, fig. 2. 
a. Original. From black argillaceous.slates, collected by Professor Hark- 
ness, and presented by him to the Museum, Geological Survey of Ireland. 
Uprer LiuAnpEILo.—‘Graptolite shale,” Duffkinnell, Dumfriesshire, south 
of Scotland, with Diplograpsus pristis on same slab. 
b. Original. A portion of one of these Graptolites enlarged, showing double 
line of canal, and the closely set series of prominent serratures or cellules. 
ce. From the enlarged figure in Memoirs Geological Survey, vol. iii., pl. 
xi. A, fig. 2. 
LOWER Tana iantaaieics, South Caernarvonshire, id., p. 329, 
Fic. 2.—a, b. Grarrotiraus Nitssoni, Barrande. 
Die Graptolithen, by Prof. Geinitz, 1852, p. 35, pl. ii., figs. 17-20, 24 
28-32. 
G.' tenuis, Portlock, Geol. Report of Londonderry, &c., pl. xix., fig. 7. 
G. Nilssont, Harkness, Journ. Geol. Soc., vol. vi., p. 61, pl. i., fig. 7. 
a. Original. Natural size. 
b. enlarged ; from black slates, Upper Llandeilo Flags. Little Queensberry 
Burn. ; 
LuanpEiLo Fracs.—Dumfriesshire, Ayrshire (?) Scotland; black slates, 
(?) Llandeilo, Belvoir, Co. Clare (?) Balbriggan, Co. Dublin, in shales; 
(?) Caradoc, Kilnacreagh, near Six-mile Bridge, Co. Clare ; Reafadda ; 
Garrangreena, and other localities near Borrisoleigh, Co. Tipperary ; 
also Desertcreat, Tyrone ; as G. tenuis, Portlock, Rep. cit. 
, 2, 
Fic. 3.—a-f. DIPLOGRAPSUS PRISTIS, Hisinger, sp. 
Prionotus pristis and scalaris ; His. Leth. Suec., p. 113, pl. xxxv., figs, 4, 5. 
G. foliaceus, Harkness, Journ. Geol. Soc., vol. vii., pl. i., fig. 18. 5 
a. Original. From a piece of black fissile slate, showing the abundance of 
these fossils, which are impressed upon each other throughout every layer. 
These Graptolites are generally white, and distinctly visible upon the black 
slate ; in some of the beds they are stained pink, the cleavage joints in the 
