EXPLANATION -OF PLATE LXVII. 



Pleuracanthus (? species). 



(Natural size.) 



Figure 



1. Shoulder girdle, with parts of the branchial arches. 



a. Left scapular arch. 



b. Eight scapular arch. 



c. Left branchial arches. 

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rf. Eight branchial arches. 

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e. Hyomandibular bone. i 



/. ? Base of attachment for the spine. 



g. Gill-rakers (stemmatoid ossicles) derived from the gill-arches. 



Formation and Locality. — Low Main Coal Seam, Newsham, Northumberland. 

 Ex coll. — Atthey Collection, Museum, Newcastle-on-Tyne. 



2. Bones of upper surface of the cranium. 



a. Parieto-frontal plates. 



b. Occipital. 



c. Lateral occipitals. 



d. Postero-lateral plates, completing the posterior margin of the cranium. 

 e.f. Intermediate plates between the parieto-frontals and the lateral plates, g. h. 



g. h. Lateral plates ; g. on the left side in fig. 2 is covered by the displaced plate d. 

 i. Anterior plates over the snout. 

 X. Small median hexagonal plate. 

 or. Orbits. 



2(1. Eestoration of No. 2. The letters above apply to this figure. 



3. Underside of the occipital plate. 



Formation and Locality. — Low Main Coal Seam, Newsham, Northumberland. 

 Ex coll. — William Dinning, Newcastle-on-Tyne. 



[6] 



