76 OLD RED SANDSTONE FISHES. 



that of its Scottish representative. Nor can I agree with him in calling the 

 surface tubercles "large," at least in comparison with those of A. ornata. 



Mr. Woodward also suggests by means of a ? the possible identity of Agassiz's 

 A. Malcolmsoni, from Scat Craig, with the species under consideration; but 

 judging from Agassiz's representation of the former I do not think that possible, 

 and unfortunately the original of that figure seems to be lost. 



History. — The original specimen, collected by Dr. Malcolmson in Nairnshire, 

 and now in the Museum of the Geological Society of London, was figured by 

 Agassiz as Coccosteus maximus, and considered by him to be a median ventral 

 plate. 1 It was, however, rightly interpreted by Pander as a median dorsal of 

 Asterolepis, in the extended sense in which he used this term ; while Hugh Miller, 

 too, alluding to Agassiz's figure, says, " From its appearance I would be more 

 inclined to regard it as the hexagonal dorsal plate of Pterichthys major." 



" Pterichthys major " was, indeed, up till very lately used as a very convenient 

 term by collectors wherewith to designate indiscriminately every fish-plate of any 

 size occurring in the Scottish Upper Old Red Sandstone, and as " Pterichthys 

 major " I found these Nairnshire plates universally known, when I took up their 

 study in 1888. I very speedily found, however, that they represented a very 

 different creature from the Pterichthys (Bothriolepis) major of the adjoining 

 district of Elgin, and that its nearest ally was the Asterolepis ornata of the 

 Russian Devonian. Since then I have, by assiduously collecting at Nairn every 

 summer, brought together an important series of its remains, which has furnished 

 the material for the following description. 



Geological Position and Locality. — Only in the Upper Old Red Sandstone 

 of the immediate vicinity of Nairn, as at Seabank and Kingsteps Quarries. 

 The original specimen is said to have come from Boghole. It is remarkable that 

 while Asterolepis maxima is unknown in those strata round Elgin which are 

 characterised by Bothriolepis major, not a single remnant of any species of Bothrio- 

 lepis has ever been found in the Asterolepis -bearing beds at Nairn. Other fish- 

 remains are very rare in these beds, but such as I have obtained lead me to suspect 

 that we have here to deal with quite a different fauna from that of the closely 

 adjoining district of Elgin ; it remains, however, for the Geological Survey to 

 settle the stratigraphical relationship of the beds. 



Special Description of Asteeolepis maxima. 



General Form. — Several specimens showing the form and proportions of the body 

 have occurred, of which the largest and best, unfortunately wanting the arms, is 



1 This is in all probability the same plate as that to which in 1838 Dr. Malcolmson applied the 

 MS. name, Cephalaspis Gordonii, see ' Quart. Journ. Geol. Soc.,' vol. xv, 1859, p. 344. 



