48 Proceedings of the Royal Physical Society. 



mistake of Agassiz, misled as he was by their mere external 

 sculpture, consisting of small tubercles with stellate bases. 



For, that " Aster olepis " cannot be applied to any of the 

 remains from Dorpat represented by these casts, is uncon- 

 sciously shown by Agassiz himself, inasmuch as he figured 

 as " Asterolepis ornata," Eichwald, a nuchal or median 

 occipital plate of unmistakable Pterichthyan character,^ 

 apparently quite unaware of the significance of its shape. 

 Nevertheless Agassiz, in some controversial remarks on the 

 subject, insisted that his Chelonichthys { = Asterolcins) had 

 nothing to do with Pterichthys ! ^ 



Now, in 1856, Asmuss published a thesis ^ in which he 

 minutely described the Dorpat fossil bones, including the 

 subjects of the aforesaid casts, and made out of them two 

 genera, Homosteus and Heterosteus, with many species. In 

 tlie former of these two, namely Homosteus, Hugh Miller's 

 fish, the so-called " Asterolepis of Stromness," is clearly to 

 be recognised. 



Upon these facts Pander insists in his " Placodermen," and 

 not only did he propose to replace " Asterolepis " by Homo- 

 steus in the case of Hugh Miller's fish, but believing 

 Asterolepis, Eichw., to be altogether identical with Pterichthys, 

 Agassiz, as the name is undoubtedly prior, he proceeded to 

 cancel the latter name altogether. 



Naturally Pander's views excited opposition in this 

 country, where the names brought into use by Agassiz and 

 Hugh Miller had become classic through the writings of 

 these distinguished men. Sir Philip Egerton, who does not 

 seem to me to have thoroughly understood the situation, 

 fiercely combated the proposals of Pander in the following 

 words : " Having read both sides of the question with great 

 care, my own impression is that Prof. Eichwald may perhaps 

 have included in his genus Asterolepis some fragments which 

 he subsequently ascertained (through the more perfect 

 Scotch specimens sent to Eussia by Dr Hamel) to belong to 



^ Op. ciL, tab. XXX., figs. 5, 6. 

 2 Op. cit., appendix, p. 152. 



^ Das voUkommenste Hautskelet der bishcr bekannteu Thierreiche, Dorpat, 

 1856. 



