CHAPTER VII.

Further Discoveries of the Ichthyolite Beds.--Found in one Locality under a Bed of Peat.--Discovered in another beneath an ancient Burying-ground.--In a third underlying the Lias Formation.--In a fourth overtopped by a still older Sandstone Deposit.--Difficulties in ascertaining the true Place of a newly-discovered Formation.--Caution against drawing too hasty Inferences from the mere Circumstance of Neighborhood.--The Writer receives his first Assistance from without.--_Geological Appendix_ of the Messrs. Anderson, of Inverness.--Further Assistance from the Researches of Agassiz.--Suggestion.--Dr. John Malcolmson.--His extensive Discoveries in Moray.--He submits to Agassiz a Drawing of the _Pterichthys_.--Place of the Ichthyolites in the Scale at length determined.--Two distinct Platforms of Being in the Formation to which they belong, 109-124