214 IXTRODUCTIOir TO ZOOLOGY. 



araples of fishes constructing nests, and evincing a remarkable 

 degree of care and anxiety for their young. The observations 

 of Mr. Couch prove, that, on our own shores, " nests are built, 

 in which the ova are deposited, and over which the adult fish 

 will watch till the young make their escape." On one occa- 

 sion this gentleman visited daily for three weeks a nest of the 

 Fifteen-spined Stickle-back {Gasterosteus spinachia), formed 

 of sea-weed and the common coralline, and invariably found 

 it guarded ; nor would the old fish quit its post so long as he 

 remained.* 



Means op escape, defence, and attack. — In some tribes 

 safety is to some extent secured by the colour of the skin 

 being inconspicuous. It was an old behef, when the real 

 fructification of the ferns was unknown, that the possession of 

 the seed gave supernatural powers of concealment ; and hence 

 Shakespeare says : — " We have got the fern-seed ; we walk 

 invisible." Without possessing the fern-seed, there are cer- 

 tain fishes that enjoy, to some extent, the gift which it was 

 supposed to bestow ; and such fishes are living in great abun- 

 dance on our own shores. We allude to some of the most 

 common flat-fishes. Let any one try to see them as thev lie 

 upon the bottom, and he will be convinced it is not an easy 

 matter. When in motion they are of course detected, and 

 occasionally the white side of the body shows for an instant as 

 they ghde along ; but as soon as they stop, and by the action 

 of the fins have settled down into the sand, they are so similar 

 in colour to the surface on which they rest that they escape 

 detection, unless the eye has watched the movement. All 

 parts of the beach, are not, however, of the same material, and 

 therefore are not of the same colour ; but, whatever it may be, 

 the upper surface of the fish exliibits a correspondence which 

 is very remarkable. We have seen it of a uniform dark tint, 

 similar to that of the muddy bottom on which the fish had been 

 found ; while on others it was of a mottled or pepper-and-salt 

 colour, like the gravel of the little bay in which it had been 

 captured. 



The Flying-fish springing into the air when pursued by the 

 Bonito, is an example of a difierent mode by which danger is 

 avoided. Others, however, do not content themselves with 



* Notes on the Nidification of Fishes, bv R. Q. Couch, Esq., published in 

 " The Zoologist," vol. ii. p. 795. 1844. 



