THE GEOLOGICAL SURVEY OF SCOTLAND NEAR GULLANE. 105 



There can be no doubt that this is the fish to which Agassiz originally applied the 

 term Megalichthys, in allusion to the great bulk which it must have attained, as testified 

 to by the gigantic teeth and scales, which were the first of its relics to come into the 

 hands of Dr Hibbert ; and there can also be no doubt that, according to the strict laws 

 of nomenclature, Megalichthys is still its legitimate generic name. It is true that 

 Agassiz confounded its remains with those of a rhombic-scaled Osteolepid, which he 

 afterwards (1844) described and figured under the name of Megalichthys Hibberti, 

 while erroneously relegating the original Megalichthys to the genus Holoptychius. 

 But priority for the application of the name Megalichthys to the fish now under con- 

 sideration was secured eight years previously by the fact that Hibbert, in pi. viii. of 

 his well-known Burdiehouse memoir, quoted above, figured under that name one of its 

 large teeth as fig. 1, while the rhombic scale of the Osteolepid appeared on the same 

 plate as fig. 3. I am consequently of opinion that I was wrong when in 1884 * I said 

 that, " though it may be a matter of regret that it "— the genus now known as Rhizodus 

 — " did not retain the name Megalichthys, the laws of nomenclature do not admit of 

 any alteration now " ; and that Mr 0. P. Hay is technically right in wishing to restore 

 that naine to the "big fish" of the Scottish Lower Carboniferous period. But the 

 inconvenience which would be caused at the present time by the replacement of 

 Rhizodus by Megalichthys would be such that I prefer meanwhile to adhere to the 

 current nomenclature. 



Family Ccelacanthid^:. 



Genus Ccelacanthus, Agassiz. 

 Ccelacanthus, sp. indet. 



Since my preliminary note on the Gullane fishes was written, various fragments of 

 a species of Ccelacanthus have occurred in the highest or " Crustacean " bed, but 

 unfortunately none are sufficiently perfect to enable one to refer them to a known 

 species, or to found a new one for their reception. The species must have attained a 

 respectable size for a Ccelacanthus, as some of its scales are nearly § inch in antero- 

 posterior diameter ; their exposed surface is covered with an ornament approximately 

 similar to that in C. elegans, Newb. (lepturus, Ag.), but to all appearance finer and 

 more delicate. The sculpture of the head bones is not shown in any of the specimens, 

 so that no satisfactory comparison with other species can as yet be obtained. 



Bed c. Collected by Mr Macconochie, and also found by Messrs R. Dunlop and 

 Angus Peach. 



*Geol. Mag. [3], vol. i., p. 115. 



