Carboniferous Limestone Trilobites. . 930 
Thorax not known. 
Pygidium circular, one-fourth wider than long, consisting of 
seventeen coalesced somites, the axis forming one-third the entire 
breadth of the shield where it joins the thorax, but diminishing 
rapidly to a rather blunt extremity at about one-fifth of its length 
from the margin of the tail-shield, which encircles it; each 
ring of the axis ornamented by a row of small granular tubercles 
(somewhat irregular in size); about eight grooved pleure are seen 
on each side the axis, each pleura forming a raised rib, extending 
to and becoming wider at its rounded extremity near the border, 
marked by a row of small tubercles,*and having a shorter inter- 
mediate rib similarly ornamented, placed behind it, in the furrow; 
the pleurz, as well as the axis of the pygidium, are convex; the 
margin has a slight narrow rim around it. 
Formation.—Carboniferous Limestone. 
Localities.—Settle, Yorkshire ; Caldbeck, Cumberland ; Castleton, 
Derbyshire; Little Island and Blackrock, Cork; Ardshanbaliy, 
Limerick. 
Many specimens have been examined from the British Museum, 
the Woodwardian Museum, the Museum of the Geological Survey of 
Ireland, and from the collections of the Rev. EH. O. de la Hey, 
Cheshire, and Mr. Joseph Wright, F.G.S., of Belfast. | 
Bracuymetopus Macooyt, Portlock, sp. 1843. Plate XIII. Fig. 2. 
Phillipsia Maccoyt, Port. 1843. Geol. Rep. Londonderry, p. 309, t. xi. fig. 6. 
Brachymetopus Maccoyi, M‘Coy. 1847. Ann and Mag. Nat. Hist. vol. xx. p. 230. 
————— ————. Morris. 1854. Cat. Brit. Foss. p. 101. 
H. Woodw. 1877. Cat. Brit. Foss, Crust. p. 27. 
Carapace not quite twice as broad as it is long, rather pointed in 
front; surface sparsely covered with small tubercles; base of the 
elabella equalling one-third the breadth of carapace, and one-half the 
length of shield (without the neck-lobe) ; basal lobes small, distinct, 
no facial suture visible; eyes large, placed on the highest point of 
cheeks and wider apart than the base of the glabella: rim of the 
head-shield ornamented by a single row of tubercles, margin strongly 
grooved or channelled, outer rim slightly raised; posterior border of 
cheeks marked by a distinct margin equal in width to the neck-lobe 
and separated by a groove corresponding to the neck-furrow; latero- 
posterior angles produced into spines. 
Thoracic somites not known. Axis of pygidium composed of 
fifteen coalesced segments, tapering to an obtuse extremity; each 
somite having about five small tubercles on the axis, and about as 
many on the eight simple lateral lobes; ribs ending abruptly near 
the margin of pygidium. 
Formation.—Carboniferous Limestone. 
Localities.—Ballysteen and Monaster, Ireland. 
Specimens of this species have been examined from the Museum 
of the Geological Survey of Ireland, and from the collection of Mr. 
Joseph Wright, F.G.8., Belfast. 
