68 Proceedings of the Boycd Fhysiccd Society. 



searches of Dr Hibbert in the quarries of Burdiehouse, though 

 indeed some of its remains had long previously been figured 

 by Ure in his " History of Euthergien and East Kilbride." 

 Uncontrovertible evidence of this may be found by referring 

 to the Proceedings of the British Association for 1834, and 

 to Dr Hibbert's original memoir on the Burdiehouse Lime- 

 stone, published in the Transactions of the Eoyal Society of 

 Edinburgh, vol. xiii., 1 835. But with the remains of this enor- 

 mous creature were also associated and confounded certain 

 rhombic glistening scales, belonging really to a considerably 

 smaller fish of a totally different genus, and when Agassiz, 

 subsequently to the meeting of the British Association at 

 Edinburgh in the year above quoted, found in the Museum 

 at Leeds a head of this latter form, or at least of an allied 

 species, he adopted it, by description and by figure, as the 

 type of his Megalichthys Hihberti,^ relegating the other to the 

 genus Holoptychius. This latter, the real '' big fish," is now 

 known as Bhizodus Eihherti, the founder of the genus being 

 Professor Owen ; and though it may be a matter of regret 

 that it did not retain the name Megalichthys, the laws 

 of zoological nomenclature do not admit of any alteration 

 now. 



The brilliantly enamelled scales, head-plates, and teeth of 

 Megalichthys are among the commonest vertebrate remains 

 found in the estuarine beds of the Carboniferous epoch in 

 Great Britain ; nevertheless specimens showing the fish itself 

 in any but a very fragmentary state are rare, and though the 

 head is very well known, from the magnificent specimen at 

 Leeds figured by Agassiz, no concise description of the con- 

 figuration of the body or of the arrangement of the fins has 

 yet been given. It was classed by Agassiz in his hetero- 

 geneous group of " Sauroides," but the resemblance of its 

 scales and head-plates to those of the Old Ked Sandstone 

 genera Osteolepis and Biplopterus did not escape the attention 

 of Sir Philip Egerton, who in Morris's " Catalogue of British 

 Fossils " proposed its reference to the family of " Sauroidei- 

 dipterini" (Sauro'ides-dipteriens), instituted by Agassiz for 

 Dipterus and the genera just mentioned. From this group, 

 1 Poissons Foss., vol. ii., pt. 2, pp. 89-96, PI. 63, 63a, and 64. 



