IN THE MANCHESTER MUSEUM. 31 



Diplopterus Agassizii, Traill, 1841. 



1841. Diplopterus Agassizii, Traill, Trans. Roy. Soc. Edin., xv., p. 89. 



1892. ,, ,, Traquair, Ann. and Mag. Nat. Hist. (6) vi., 



p. 484, fig 3. 



Under surface of the head of Diplopterus Agassizii, reduced one-third. 



m.n., mandible; i.op., interoperculum ; j., principal jugal ; 



m.j., median jugal ; l.j., lateral jugal plates. 



Impression of the fish lying on its back. The lateral 

 jugals are particularly well marked ; there are five on the 

 right side, four on the left. 



Achanarras, Caithness. 



Old Red Sandstone. Coll. Edimrds. 



Pleuracanthus laevissimus, Agassiz, 1837. 



1837. Pleuracanthus lavissivms, Ag., Poiss. Foss., iii., p. 66. 

 1892. „ „ Davis, Trans. Roy. Dublin Soc, iv., p. 730, 



pi. Ixx., fig. 8. 



Figured specimen of a Gill-raker. A small bony ossicle, 



bearing a series of fine-pointed denticles. 



Locality (?) 



Middle Coal Measures. 



Pleuracanthus undulatus, J. W. Davis, 1892. 



1892. Pleuracanthus 7indulatus, Davis, Trans. Roy. Dublin Soc , N.S., iv., 



p. 737, pi Ixxii., fig. 16. 



Type. — Spine 12-3 cm. in length, bearing upon its upper 

 posterior surface two rows of denticles widely separated 

 and diagonally arranged, those of one row being slightly in 

 advance of those of the other ; readily distinguished by the 

 larger and widely separated posterior denticulation. 



Thin-bed Coal, Fulledge Colliery, Burnley, Lanes. 



Middle Coal Measures. Donor, G. Wild. 



