Actinopterijgii — Aciheospcmdyli. 



107 



moiitli and conical teeth. The thick-scalecl EvgotatJius (Fig. 151) 

 and the thin-scaled Catnrns (Fig. 152) loth range thronghotit 

 the Jurassic, the specimens from the Louver Lias of Lyme 



::,f=^='-«;>5>,^.^i^-' ' 



Fig. 1 



,Ag.: Lithographic Sti'ne, Eavaria. [Scales Cimittcd. 



Regis and the Lithographic Stone of Bavaria being particularly 

 fine. Keorliomholepis is an interesting fish from the English 

 Chalk and Wealden, -with rhombic enamelled scales and disc- 

 shaped vertebra?. 



The Amiidge are first cei-tainly represented in the Upper 

 Jurassic. 3[egalnrus, from the Lithographic Stone of Bavaria 

 and France and from the English Pnrbeck Beds, is very similai' 

 to Amia but has a shorter dorsal fin. The existing genns is 

 represented by fine specimens from the Lower Miocene of 

 France, and is also known in Geimiany. Detached vertebra) 

 are shown fi-om the Lower Tertiaries of the Hampshire Basin. 



A family of Amioids which curiously mimic the modern 

 sword-fishes, ranges throiighout the Jurassic and Cretaceous 

 periods, and is represented by Facliycormns (Upper Lias), 

 Hypsoconnns (Oxfordian and Kimmeridgian), and Protosphyrceno 

 (Upper Cretaceous), besides other genera. The notochord 

 is persistent, but to strengthen the trunk the vertebral arches 

 are multiplied and very closely arranged ; the powerful forked 

 tail is supported by a triangular expansion of one of the hfemal 

 bones ; and the snout gradually becomes elongated until it is 

 a formidable weapon in Protosphyrccna. 



"Wall-case, 

 No. 13, and 

 Table-case, 

 No. 44. 



Wall-cases, 

 Nos, 13, 14. 

 Table-case, 

 No. 45. 



SuF.-ORDEi; III. — Aetheospondyli. 



Next to the Pachycormida?, in an uncertain position, are Wall-case 

 placed the Aspidorhjaichidte and the modern LepidosteidEe, the No. 14, and 

 former ranging from the Lower Oolites to the Upper Chalk, the ^^^^fz*^*^®' 

 latter exclusively Tertiary. Aspidorhynchns (Fig. 153), with 

 prominent rostrum, is represented by a fine series of specimens 

 from the Lithographic Stone of Bavaria ; the closely-related 

 Belonostomus, with elongated jaws but little or no prominent 

 rostrum, is shown both from this formation and in a unique 



