134 A fish's nest. 



not deserving of. For, though it is so abundant in 

 every shallow pool that idle little boys, on Saturday 

 half-holidays, make it the constant object of their 

 sporting excursions, as their metropolitan cousins 

 resort to the suburban canals to catch Tittle-bats, — 

 the Tansy is worth putting into an Aquarium. Some 

 specimens are ugly enough, it is true, both in form 

 and colour ; but others are quite attractive : they vary 

 much from an uniform blackish olive, to a mixture of 

 bright colours, as green, white and yellow ; and the 

 eyes are almost always beautifully brilliant, the large 

 iris being of a vivid scarlet. It is an amusing fish in 

 captivity, displaying a mixture of impudence and 

 timidity, coming out fiercely to snatch a morsel of 

 food from before a fellow fish's mouth, and then darting 

 charily under the shadow of a rock to eat its treacher- 

 ously gotten booty. 



What makes this fish more than usually interesting, 

 is, that it is one of those species which construct an 

 elaborate nest for the deposition of their eggs and the 

 hatching of their young: — 



" Atque aTium dulcea nidos imitata sub undis." 



Ovid. 



I have not had the good fortune to meet with the 

 structure myself, and shall therefore refer my readers 

 to the details mentioned by Mr, Couch in his " Illus- 

 trations of Instinct" (p. 253 et seq.), where the con- 

 struction of the little dwelling of fragments of coral- 

 line and other sea- weeds, interwoven by silken threads, 

 its suspension from an overhanging rock, the deposi- 

 tion therein of the amber-coloured eggs, the habits 



