BRITISH FOSSILS. 



Decade IX. Plate X. 



MACROPOMA EGERTONI. 



[Genus MACROPOMA. Agassiz. (Sub-kingdom Verlebrata. Class Pisces. 

 Order Goniolepidoti. Family Cselacantbi.) Caudal fin very large, rounded. Two dorsal 

 fins, one over tbe interspace between the pectoral and ventral fins, the other opposed to 

 the interspace between the ventral and anal fins. The rays armed with marginal spines. 

 Scales enamelled, imbricated, rounded posteriorly, and tuberculate. Teeth large and 

 conical, intermixed with smaller ones. Vomer and palatines dentigerous.] 



Macropoma Egertoni. Agassiz. Poiss. Foss. vol. 2, part 2, page 186. 



At the time when Professor Agassiz was engaged upon his great 

 work on the Fossil Fishes, the materials crowded in upon him in 

 such abundance that he found it impossible to comprise them all in 

 one publication; with any prospect of completing it in reasonable 

 time. He therefore dete] 'mined to finish his original work in five 

 volumes, and to postpone the descriptions of those species he could 

 not incorporate, to form a series of supplementary monographs. He 

 was only able to issue one of these, that on the fishes of the Old Red 

 Sandstone, before his engagements in the United States put a stop 

 to his ichthyological labours on this side the Atlantic. As there 

 seems to be little chance now of his resuming the subject, it appears 

 to me desirable that some of the most characteristic genera and 

 species which vvere named by him, but not described, should no 

 longer remain in our catalogues undefined. I have therefore selected 

 a few of the most striking forms for description in this Decade. 

 The genus Macropoma is one of the most singular in the whole 

 range of fossil ichthyology. We owe its discovery to the inde- 

 fatigable zeal and scientific skill of the late Dr. Mantell, who 

 described the only species then known under the name of Amia 

 Lewesiana. Professor Agassiz subsequently determined it could not 

 be considered as belonging to that genus, but that it constituted a 

 new generic type, to which he gave the name now adopted. The 

 specific name given by Dr. Mantell ought to have been continued, 

 but a departure from the rigid rule of scientific nomenclature was 

 [ix. X.] 9 L 



