FISH-LIVERIES, AND WHY THEY A HE WORN. 69 



Next appears a discontinuity in these fins, gaps 

 appearing which isolate certain portions. The 

 cause of the gaps is unknown, but is probably in 

 some way connected with the undulating move- 

 ments of the fish. From simple balancing — we 

 next proceed to movable balancing — organs 

 which take on the new duties of steering. 

 These become more and more perfect as we 

 work up the scale of fish life. 



In the earlier part of this chapter we saw 

 how these fins, gradually, in response to new 

 demands, became transformed sometimes into 

 organs of touch, sometimes into weapons of 

 oflfence, and sometimes into organs of prehen- 

 sion, as in the suckers of the gobies, lump-fish 

 and remora. 



CHAPTER VII. 



FISH-LIVERIES, AND WHY THEY ARE WORN. 



Probably in thinking of birds we do so as often 

 as not in terms of their most conspicuous forms. 

 Thus we recall such birds as peacocks, pheasants, 

 parrots, canaries, and kingfishers at once ; a 

 further sifting of our memories brings up from 

 its darker recesses more sombre forms. Now in 

 dealing with the birds in this series of little 

 volumes, it was pointed out that this colouration 

 had a deep significance. Thus, we found that it 

 often happened that in the case of a brilliantly 

 coloured bird it is the male only which is 

 resplendent, whilst the female is quite dull. 



