72 OLD RED SANDSTONE FISHES. 



name without description had been announced by Sir R. I. Murchison to the 

 British Association at its meeting at Glasgow in August, 1840. 1 



To the Russian remains Agassiz gave somewhat later the name Chelonichthys? a 

 name which he, however, afterwards withdrew 3 in favour of Eichwald's A sterolepis, 

 to which priority was due. But unfortunately he also identified generically with 

 Eichwald's Asterolepis certain other remains from the Devonian strata of Dorpat, 

 some of which were first figured by Kutorga as Trionyx and Ichthyosauroides? and 

 of which a considerable number, collected by Asmuss, were reproduced in plaster 

 and copies sent to Agassiz, who figured a number of them as bones of " Asterolepis"* 

 Now some of these were generically identical with the creature of whose bones 

 and buckler many specimens from Thurso, collected by Robert Dick, came into 

 the possession of Hugh Miller, and thus it came to pass that the writer of the 

 ' Footprints ' figured these remains as belonging to Asterolepis, a genus to which 

 they bad no resemblance save in the stellate tuberculation of the external 

 surface. 



That Asterolepis, Eichwald, was closely allied to Pterichthys, and had nothing 

 to do with any of the Dorpat bones represented by Asmuss's casts, is unconsciously 

 shown by Agassiz himself, inasmuch as he figured as Asterolepis ornata, Eichwald, 

 a median occipital plate of unmistakably Pterichthyan character, 6 apparently quite 

 unaware of the significance of its shape. Nevertheless, in some controversial 

 remarks 7 into which he entered with Eichwald on the subject, he insisted that his 

 Chelonichthys ( = Asterolepis, Eichw.) had nothing to do with Pterichthys. 



In 1857 Pander published his classic work ' Ueber die Placodermen des 

 devonischen Systems," in which, from isolated and beautifully uncompressed and 

 solid plates from Livonia, he skilfully reconstructed and minutely described the 

 Asterolepis ornata of Eichwald. Going also extensively into the synonymy of the 

 subject, he cited no less than eighteen other named genera as identical with 

 Asterolepis in whole or in part. These were — 



Bothbiolepis, Eichw. Pamphbactus, Agass. 



Chelonichthys, Agass. Homothobax, Agass. 



Glyptosteus, Agass. Placothoeax, Agass. 



Ptebichthys, Agass. Odontacanthus, Agass. 



1 * Brit. Assoc. Eep.,' x, 1840, Trans. Sect., p. 99. 



2 ' Poissons fossiles,' vol. i, 1884, p. xxxiii (name only). 



3 ' Poiss. foss. vieux Gres rouge,' 1845, p. 89. 



' 4 ' Beitrag zur Geognosie und Palaontologie Dorpats,' St. Petersburg. 1835 — 37. 



5 ' Poiss. foss. vieux gr. rouge,' pi. xxxii. 



6 Ibid., pi. xxx, figs. 5, 6. The other fragments figured on the same plate as Asterolepis ornata 

 (figs. 2 — 4, 7 — 9) in all probability belong also to the same creature. 



7 Ibid., Appendix, p. 151 ; in reply to remarks by Eichwald in ' Karsten's Archiv,' vol. xix, 

 1845, p. 667. 



