KONGL. SV. VET. AKADEMIENS HANDL. BAND. 20. N:0 9. 5 



them definitely to a genus. I shall describe those whicli come from the red sand- 

 stones (Upper Silurian) of Dickson Bay in one chapter and those from the brown 

 shales (Upper Devonian or Carboniferous) of Mimers dal in a second chapter. 



A. Fish remains from the upper Silurian sandstone of Dickson Bay, Spitzbergen 



1. SCAPHASPIS' Nathorstii, n. sp. Figs. l, la, 2, 3, 3a. 



Characters. Cephalic shield resembling that of Scaphaspis Lh)3'dii from the Corn- 

 stones of Herefordshire — but somewhat l^roader and shorter. The fine parallel 

 grooving of the outer surface resembling that of »Se. Lloydii but presenting charac- 

 teristic »beading» of the grooves at the margin of the shield (tig. 1 a). 



The evidence on which this species is based is very satisfactory. The fine slab 

 drawn in iig. 1. contains five more or less complete head-shields of Scaphaspis Nathor- 

 stii. Two other specimens (fig. 2 and 3) contain respectively two shields and one 

 shield — sufhciently well preserved. 



2. CEPHALASPIS. Sp. Figs. 4, 4 a, 5. 



The specimens drawn in tig. 4 and 5, furnish ample evidence of a fish belonging 

 to the genus Gephalaspis, but are not sufficiently perfect to warrant any attempt at 

 specific identification, on account of the surface ornamenta.tion not being preserved. 

 The smaller specimen is possibly identical with the Cephalaspis Agassizii Länk. of the 

 Herefordshire cornstones. The tuberculation of the right horn of the shield (magni- 

 tied in fig. 4 a) favoui-s this supposition. 



On the other hand, the larger fragment is verj' probably to be referred to Ce- 

 phalaspis (Zenaspis) Salweyi, Egerton, also found in the Herefordshire cornstones. 



•3. LOPHOSTRACON Spitzbergense. nov. gen. et spec. Fig. 6. 



The remarkable fragment drawn in hg. 6 deserves to be recorded under some 

 designation — hence I have coined the name Lophostracon which has reference to the 

 deep fluting or ridged structure of the piece of bony tissue before us. 



It is quite impossible to say anything more with regard to this fragment than 

 that it indicates a large and peculiar hsh. I know of no similarly ornamented bony 

 remains from the Old Red or from the Upper Silurian of Britain nor from equivalent 

 beds in other pai-ts of Europé. 



B. Fish remains from the Upper Devonian or Lower Carboniferous(?) strata 



of Mimers Valley. 

 1. SCALES. 



In figs 7, 8, 9, 10, 11, 12, is drawn a series of scales from the shales of the 

 Mimers Valley which all belong to one species. I have not ol)served in the specimens 



1) For definition of this genus see »The Fossil Fishes of the Old Red Sandstoneu. Part. I. The Cephal- 

 aspidfe by E. Ray Lankester. Palseontogr. Society. Vol. XXI. 



