98 



THE FAR PAST. 



" double-fin ;" the osteolepis, or "bony-scale;" the asterolepis, 

 or "star-scale;" and the Iwloptycldus, or "all-wrinkle," so 



1, Acanthodes : 2, Clirnatius ; 3, Diplacanthus. Forfarshire. 



called from the wrinkle-like sculpturing that adorns its large 

 enamelled scales. The majority of these fishes are small, or 

 of moderate size ; and even the largest of them, the holop- 

 tychius and asterolepis, do not greatly, if at all, exceed 

 the dimensions of a full-grown cod-fish. Nor would 

 they startle by their forms, were they recalled to take their 

 place among existing fishes. The little armed bull-head of 

 our own shores is encased in as marvellous, and even more 

 highly ornamented armour than the cephalaspis ; the ostra- 

 cion, or trunk-fish of the Indian ocean, is encased in a 

 bony box, as curiously fabricated as that of the pterichthys 

 or coccosteus ; the spines of the balistes and sea-snipe are 

 as formidable weapons as the ichthyodorulites of the dipla- 

 canth; and the scales of the bony-pike of South America, 

 or the polypterus of the Nile, glitter with enamel, and are 

 as quaintly sculptured as those of the osteolepis or holop- 



