EXPLANATION OF THE PLATES AND WOOD-CUTS. 



WOOD-CUTS ILLUSTRATIVE OF THE PAPER. 



No. I. Shifted quartz veins in a perpendicular clifF at Mycreeny, between Blind 

 Harbour and Erris Head : p. 138. 



No. 2. Diagram explanatory of No. 1. The portion folded back is intended to re- 

 present the surface, at the top of the cliff; and the other part of the diagram the 

 cliff as represented in No. 1 . In using the diagram, the portion folded back should 

 be held at right angles to the other : p. 159. 



No. 3. Strata of mica slate bent over projecting masses of trap at Attatovick Point : 

 p. 162. 



No. 4. Contorted strata of shale and grit, north of Poolaclogher : p. 165. 



No. 5. Trap dyke in carboniferous limestone east of Killala Bay : p. 167. 



PLATE XIL 



Illustrates Mr. Broderip's memoir on some fossil Crustacea and Radiata found at 

 Lyme Regis : p. 171 to 174. 



Figs. 1. 2. Coleia antiqua : p. 172. Fig. 1. represents a young individual in the col- 

 lection of the Geological Society. 



Fig. 2. a. Peduncle of mesial antennae. 



b. Internal setae. 



c. External setae. 



d. Lamelliforra appendage of the peduncle of the external antennae. 



e. Base of the terminal setae of the external antennae. 

 Fig. l.f.f. Eyes. 



Fig. 1. 2. g. g. Thorax. 



Feet. 

 First pair or chelce, which have been displaced in both specimens, and pushed for- 

 ward in the smaller one. 

 Fig. 2. h. Humerus. 

 i. Cubitus. 

 k. Carpus. 

 I. Manus. 

 m. Digitus. 

 n. Pollex. 

 Fig. 1. 0.0. Indications of the other feet, shown by the partial removal of the thorax. 

 p. Post abdominal segments. 

 q.q. Caudal natatory lamellae. 

 Figs. 3. 4. Remains of a macrourous Decapod, allied to the Salicoques of Latreille : 

 p. 173. 



a. a. Point to the impressions of the branchiae, exposed by the removal of the 



lateral portions of the thorax. 



b. b. Terminal spines of the post abdominal segments. 



Fig. 5. Ophiura Egertoni from the collection of Mrs. Murchison. The figure repre- 



