PEDIGREES. 185 



is distinguished by the remarkable resemblance 

 which it bears to the modern sword-fish, with 

 which it cannot possibly be related. In Prota- 

 sphyrcenea of the upper Cretaceous period, the 

 sword — which has been gradually increasing in 

 length in different genera, beginning with a 

 form known as Pachycormus (thick hide) of the 

 Upper Lias, and passing through Hypsocormus 

 of the Kimmeridgian — was as formidable a 

 weapon as in the living sword-fish. This curious 

 resemblance is another instance of parallelism 

 (pp. 13, 173). 



It will be sufficient to show the importance 

 of the bow-fin family to remark that this is 

 regarded as probably the group from which the 

 majority of the modern fishes may be traced. 



Of uncertain relationships are the American 

 bony-pikes, or gar-pikes, Lepidosteus, and their 

 fossil kindred. The living Lepidosteus — of 

 which genus there are three species — like the 

 bow-fin, is at present confined to the fresh waters 

 of North America; but, like the bow-fin, once 

 enjoyed a much wider distribution, its remains 

 occurring with great frequency in Europe — in 

 the Eocene and Lower Miocene periods. The 

 living gar-pike in many respects resemble the 

 fringe-finned Polypterus (p. 178), being similarly 

 clad in heavy armour. Polypterus, Amia and 

 Lepidosteus are each alike interesting as the 

 isolated survivors of diff'erent branches of extinct 

 groups. The living gar-pike, or bony-pike, some- 

 times attains a length of six feet. They are 

 carnivorous. In South Carolina Mr Bashford 

 Dean tells us he has known it to occur in such 



