CHAPTER IV.

The Elfin-fish of Gawin Douglas.--The Fish of the Old Red Sandstone scarcely less curious.--Place which they occupied indicated in the present Creation by a mere Gap.--Fish divided into two great Series, the Osseous and Cartilaginous.--Their distinctive Peculiarities.--Geological Illustration of Dr. Johnson's shrewd Objection to the Theory of Soame Jenyns.--Proofs of the intermediate Character of the Ichthyolites of the Old lied Sandstone.--Appearances which first led the Writer to deem it intermediate.--Confirmation by Agassiz.--The _Osteolepis_.--Order to which, this Ichthyolite belonged.--Description.--_Dipterus._--_Diplopierus._-- _Cheirolepis._--_Glyptolepis_, 55-78