IN THE CARBONIFEROUS ROCKS OF THE EDINBURGH DISTRICT. 



695 



conditions, for the Abden bed is still more obviously of marine origin, and lies close 

 below limestone containing hinged brachiopods, corals, etc. 



Loanhead Ironstone, No. 1. — This ironstone (see PI. II.) lies between "Brown's" 

 coal and the " Glass " coal, nearly in the middle of the Edge Coal Group. Above it is 

 also a shale with Lingula squamiformis, and, including the species found both in that 

 and in the ironstone and accompanying " parrot," the list is as follows : — 



Pleuroplax falcatus. 

 Pleuroplax, sp. 

 Oracanthus armigerus. 

 Tristychius arcuatus. 



„ minor. 



Acanthodes, sp. 



Rhizodtcs Hibherti. 

 Ccelacanthus Abdenensis. 

 Ctenodus interruptus. 

 Elonichthys Robisoni. 

 Nematoptycliius Greenocki. 

 Eurynotus crenatus. 



All the species in the above list we have already noted from beds below, but it 

 is of interest to find that along with the Lingula we have again the Pleuroplax, 

 Oracanthus, and Ccelacanthus of the ironstone shale last mentioned. 



Borough Lee Ironstone, or Loanhead Ironstone, No. 2. — This ironstone is situated 

 above the " Great " Seam near the top of the Edge Coal Group. It is the most produc- 

 tive in species of fishes and fish-remains of the beds which has turned up in the 

 Lothians, and has yielded no fewer than thirty-five species, some of which have not 

 been found elsewhere. They are as follows : — 



Diplodus parvulus, Traq. 

 Pleuracanthus elegans, Traq. 



„ gracillimus, Traq. 



„ horridulus, Traq. 



„ fastigiatus, Davis. 



Dicentrodus bicuspidatus, Traq. 

 Callopristodus pectinatus (Ag.). 

 Gyracanthus nobilis, Traq. 



„ Youngi, Traq. 



Aganacanthus striatulus, Traq. 

 Tristychius arcuatus. 



„ minor. 



Sphenacanthus serrulatus. 

 Cynopodms crenulatus. 

 Euctenius elegans, Traq. 

 Megalichthys, sp. 

 Ehizodopsis, sp. 



Rhizodns Hibberti. 

 Strepsodus striatulus. 

 Uronemus splendens, Traq. 

 Ctenodus interruptus. 



„ angustulus, Traq. 

 Sagenodtts quinquecostatus. 

 Eurylepis Scoticus, Traq. 

 Gonatodus parvidens, Traq. 

 Drydenius insignis, Traq. 

 Elonichthys Robisoni. 



„ pectinatus. 



Rhadinichthys ornatissimus. 



„ carinatus. 



Nematoptycliius Greenocki. 

 Cryphiolepis striatus, Traq. 

 Eurynotus microlepidotus, Traq. 

 Cochliodont spine, undet. 



Leaving Diplodus parvulus and JEuctenius elegans out of consideration, as they 

 may have belonged to one or other of the Pleuracanthi here noted, we find in this list 

 thirty named species, of which fifteen have already occurred in the strata below. 

 Some — namely," Tristychius arcuatus, Rhizodus Hibberti, Elonichthys Robisoni, 

 Rhadinichthys carinatus, Nematoptycliius Greenocki — extend down even into the 

 Wardie shales, in which all, except the first, are common species. On the other hand, 

 however, fifteen species make their first appearance here, and of these six have not yet 

 been found elsewhere. 



TRANS. ROY. SOC. EDIN., VOL. XL. PART III. (NO. 28). 



5 K 



