82 me. j. w. kiroy osr pebmias Ersn AND riANTS. 



Fill well Fish-bed were similar to those that obtained during the 

 accumulation of the Marl-slate in the early part of the Permian 

 era. The characteristic fossils of the Marl-slate are fishes belong- 

 ing to the genera Palceoniscus, Acrolepis, Pygopterus, Platysomus, 

 and Coelacanthus, the species of the first genus being by far the 

 most common. "With the fish occur the remains of plants, chiefly 

 belonging to TJlmannia selaginoides ; and, rarely, examples of 

 Lingula, Piscina, and Myalina. The facies of this small fauna 

 seems to me to be decidedly estuarine, though with a greater 

 tendency to approach freshwater than marine conditions ; for, 

 while the vegetable remains, which indicate terrestrial and 

 freshwater habitats, are distributed generally throughout the 

 whole of the Marl-slate, the Mollusca, which seem as certainly 

 to indicate marine conditions, are confined to a very limited area 

 in the same deposit. In the Fulwell Fish-bed we have fish be- 

 longing to the same genera, and plants belonging to the same 

 species, as those that occur in the Marl-slate, besides other plants 

 whose occurrence there is not recorded. In this bed there are no 

 Mollusca, nor is there, as I have before observed, a single trace 

 of any marine organism. It would, therefore, seem as if the 

 physical conditions of the Fulwell Bed had been even less marine 

 than those of the Marl-slate ; so that it is not unlikely that in its 

 small group of species we see part of a freshwater fauna of the 

 Permian period. 



Another inference appears warrantable in respect of the fish ; 

 that is, that the presence of so predaceous-looking a species as 

 Acrolepis among small and comparatively harmless Palceonisci evi- 

 dently indicates that the latter were pursued and preyed upon by 

 it. The association merely of these fish suffices to justify this 

 inference ; but the occasional presence of undigested remains of 

 the Palceonisci between the scales of the abdominal region of the 

 Acrolepis would as certainly seem to prove it. The occurrence 

 of so many uninjured individuals of the Palceonisci along with the 

 Acrolepis would further indicate that both the pursued and the 

 pursuers were ultimately overtaken by circumstances that ren- 

 dered powerless their instincts in one common catastrophe. 



In conclusion I would remark, that though these fossils form, 



