Carboniferous Limestone Trilobites. 483 
segments nine in number, strongly trilobed; axis wider than the 
pleuree ; the posterior portion of each segment strongly corrugated, 
and each pleura groove extending rather beyond the fulcral point ; 
the extremity of each pleura is rounded and broadly faceted ; pygi- 
dium rounded, consisting of eleven coalesced somites which in the 
axis coutinue the corrugated character of the thorax, but diminish to 
a blunt termination considerably within the border; the ribs of the 
pygidium are double and die out before reaching the edge of the 
tail-shield, leaving a somewhat wide smooth margin. Surface of 
head very finely punctate. 
Formation.—Carboniferous Limestone. 
Localities.— Bolland and Settle, Yorkshire; Forest of Wyre, 
Preston ; Millicent, Clane, Kildare; Waterford, Clonea; Derryloran, 
Tyrone; Blackrock, Dublin; and Athlone, Ireland. 
Specimens of Griffithides globiceps have been examined from the 
National Collection, the Museum of the Geological Survey of Ireland, 
from the Woodwardian Museum of Cambridge, and from Mr. Joseph 
Wright’s Collection. 
GRIFFITHIDES ACANTHTCEPS, H. Woodw. 1883. Pl. XII. Fig. 4. 
Grifithides acanthiceps, H. Woodw. sp. nov. 1883. Pal. Soc. Mon. Carb. Trilob. 
part 1. p. 32, pl. vi. figs. 2, 10, 11. 
Head-shield semicircular, produced in front, glabella very gibbous, 
overhanging the anterior margin, twice as wide in front as at the 
nuchal furrow, the whole surface strongly granulated; basal lobes 
very small, rounded; neck-furrow deep; neck-lobe rounded; fixed 
cheeks exceedingly narrow, scarcely discernible, forming a rounded 
palpebral lobe (the surface of which is granulated) over each eye, 
and a narrow rim around the glabella; eyes small, finely faceted, 
inner raised portion of cheeks granulated, margin smooth, posterior 
angle produced into long cheek-spines equal to the glabella in 
length. 
Thorax consisting of nine free segments, surface of thorax smooth 
without ornamentation; axis arched, rather wider than its pleura, 
broader next the head and diminishing very slowly to the pygidium ; 
each of the pleure strongly grooved down the centre, posterior 
portion rounded and slightly raised, anterior portion slightly 
depressed ; fulcral points distinctly marked, extremity of pleurze 
faceted in front and rounded. 
Abdemen or pygidium composed of about thirteen coalesced somites, 
border smooth, slightly channelled, ribs terminating close to border. 
Extremity of pygidium very slightly pointed. 
Formation.—Carboniferous Limestone. 
Localities.—Craco, near Grassington; Settle, Yorkshire; aud 
Castleton, Derbyshire. 
The only specimens of G. acanthiceps known to me are in the 
Woodwardian Museum, Cambridge, and in the cabinet of J. Aitken, 
iisq. 
