The Spine-finned Teleostei . 399 



vertebrae that steadily advance from the 24 to 35 of Ser- 

 ranids, retained as such by the Uranoscopidae and Gobiosoc- 

 idae, but increasing to 35 - 45 in Bleniidae and Trachinidae; 

 the tendency to partial or complete subdivision of the 

 dorsal fin, and to formation of numerous spiny rays in these 

 two subdivisions, that show all stages of increase from 

 7-12 spines of Serranids to the 40 or more of Blenniidae, 

 are characters that are most nearly explicable in terms of 

 a serranid ancestry. 



Of the 12 to 15 families recognized by recent ichthy- 

 ologists, the three which the writer would regard as nearly 

 related, and also as most primitive, are the Blenniidae, the 

 Trachinidae, and the Uranoscopidae. But the diverse and 

 striking modifications in the number and structure of parts 

 seen in the first of these, as one passes from the more 

 typical or normal to the most modified of the group, is proof 

 that rapid evolution, selection, and variation have been act- 

 ing from Miocene on to recent times. 



The distribution of such blennioid genera also as Clinus, 

 Salarias, and Blennius over the warm seas of the whole 

 world suggests that since the time of derivation from some 

 marine serranid ancestor, constant migration, new environal 

 action, proenvironal response with variation, and readapta- 

 tion, have been proceeding at a rapid rate. 



The outcome of such is that the other families of the 

 Jugulares, which show decided affinity to, as well as pro- 

 gressive or regressive variation from, the three families 

 above named, have often acquired those remarkable 

 characteristics that now distinguish them. Thus the Zoar- 

 cidae, the Gobiesocidae, the Ophidiidae, and the Batra- 

 chidae are amongst the most curious and highly modified 

 of acanthopterous fishes. But some of these again lead to 

 still more altered families or even orders. For the Batra- 

 chidae or toad-fishes evidently lead on to the Lophiidae or 

 fishing-frogs, the Ceratiidae or devil-fishes, and the Anten- 

 nariidae or anglers. The very rare — but still occasional — 

 presence of an isolated species of some of the above in 

 freshwater, as for example of Blennius vulgaris in Italian 

 lakes, or of the Cuban blindfishes Lucifiiga and Stigicola 

 in cave-waters of that island, again prove that return of 



