254 



THE CARBONIFEROUS SYSTEM. 



Fig. 77. — Placoid and Ganoid Fishes from the Lower Carboniferous.— 'Rorion Bluff. 



(a, 6, c, d) Portion of Jaw, Tooth, and Scales of Rhizodus Eardingx, Dawson— nat. size. The 

 tooth (6) is a little too slender. 



(e,/) Portion of Jaw and Scale ot Acrolepis Hortonensis, Dawson — the scale magnified. 

 {g, h) Spine of Ctenacanthus and portion magnified. 



