BOTHRIOLEPIS MAJOR. L19 



the ' Poiss. Foss. v. Geres rouge' after a drawing communicated to him by Dr. 



Malcolmson. The original specimen is stated by Agassiz to be in the Elgin Museum, 

 but Dr. Smith Woodward states that it is in the collection of the Geological 

 Society of London. Two other fragments of the pectoral appendage from the 

 same locality, and now in the Edinburgh Museum, were also described and figured 

 by Agassiz as belonging to a distinct genus, namely " Placothorax," while the 

 impressions of three plates from Alves, in the British Museum collection, were 

 referred in the same work to the Russian Bothriol&pis ornata, Eichwald. The 

 bases of the tubercles are in B. major, as we have seen, frequently stellate, a feature 

 wanting in B. ornata, so far as is known ; and if Eichwald's figure of the entire 

 anterior median dorsal plate in his species is correct, that element in B. major 

 strongly differs from it in its much greater proportional breadth. 



Another closely allied Russian form is the B. Panderi of Lahusen, of which 

 there are some fragments, from the Sjass River, in the Edinburgh Museum. From 

 these it would appear that, in many places, the tubercles, which are very frequently 

 stellate, tend to be not quite so confluent as in B. major, and that the angulated 

 flexure of the sensory groove on the premedian plate is more acute ; but more 

 cannot be said at present. 



As regards the external sculpture of B. major, it is to be noted that, as already 

 indicated in the text and borne out by our figures, there are great differences in 

 the relative fineness and coarseness of the markings. As a rule this depends on the 

 age and size of the individual, the smallest specimens having the finest sculpture 

 and vice versa, but instances also occur (see PL XXIII, figs. 5 and 6), in which plates 

 of much the same size differ markedly from each other in this respect. The same 

 remarks apply more or less to other species of Aster olepidae. 



Geological Position and Localities. — Characteristic of the middle division of the 

 Upper Old Red Sandstone of the Moray Firth area, the remains of Bothriolepis 

 major are found in all the localities for fish-remains in that series, as — 



Banks of the Findhorn River; 



Old quarries at Whitemire, near Brodie Station ; 



Carden Hill, Sweet Hillock, Rocky Park, Millstone Quarry, and Newton 

 Quarry, near Alves ; 



Redhall Quarry, near Fochabers ; 



Scat Craig ; 

 also in the uppermost or " Rosebrae " beds of the same formation at Rosebrae 

 and Laverock Loch, near Elgin. 



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