106 EXPLANATION OF THE PLATES. 
Original. Cup or Head composed of many hexagonal plates, and showing 
articulating surfaces of the arms. Carb. Limest. Derryvullan, Co. 
Tyrone. Mus. G. S. I. 
CaAkBONIFEROUS LimestonE.—Yorkshire, Bristol, Cos. Tipperary, Tyrone, 
and Fermanagh. 
ECHINOIDEA. 
Fie. 11.—a-d. Patacuinvs ELecans, If‘ Coy. 
Synop. Carb. Foss. Jrel., p. 172, pl. xxiv., fig. 2. Nobis, Journ. Royal 
Geol. Soc. Irel., vol. xi., p. 66, pl. iv. 
Original. a. Side view of shell or test. 6. Genital and ocular disk; en~ 
larged to twice natural size. c. Portion of the ambulacra, with adjoin- 
ing inter-ambulacral plates. d. Spine, enlarged twelve times; the line 
near it represents its natural size. 
CARBONIFEROUS LimEsToNE.—Lower, Hook Head, Co. Wexford. Mus. 
G.S. I. 
Fie. 12.—a, 6. Ancumocrparts Uri, Fleming, sp. 
Cidaris, Flem. Brit. Anim. C. Benburbiensis, Portl. Geol. Rep., p. 352, 
pl. xvi., fig. 10,11. Echinocrinus, M‘Coy, Synop. Carb. Foss. Irel., 
p- 174, pl. xxvil., fig. 1. Archeocidaris, Morris Cat. Brit. Foss. (1854), 
le 
Gra a. One of the central rows of inter-ambulacral plates. 6. Spine, 
Carb. Limestone (lower shales), Benburb, Armagh, and Tyrone. 
CaRBONIFEROUS LIMESTONE.— Many localities in England, Scotland, and 
Treland. 
