DWELLINGS. 173 



will apply to the back a fragment of wrack or of 

 anything which comes to hand. A little white cloak 

 with the arms of Brittany was manufactured for one 

 of these captives, and it was very amusing to see him 

 put on his overcoat when he had nothing else where- 

 with to cover himself.^ 



In these two cases which I have brought forward 

 to exhibit the rudiments of this industry, the animals' 

 reflection and will play but a small part ; even in 

 the Dromia custom is so inveterate in the race that 

 it has reacted on the animal's organisation, and its 

 four posterior legs are profoundly modified for the 

 purpose of firmly holding the sheltering sponge; they 

 no longer serve for swimming or walking. The 

 animals of which I have now to speak possess more 

 initiative ; although all do not act with the same 

 success, or show themselves equally skilful. Let us 

 turn first to the least experienced. 



An Australian bird, the Catheturus Lathami, as 

 described by Gould, is still in the rudiments, and 

 limits itself to preparing an enormous pile of leaves. 

 It begins its work some weeks before laying its 

 eggs; with its claws it pushes behind it all the dead 

 leaves which fall on the earth and brings them into a 

 heap. The bird throws new material on the summit 

 until the hole is of suitable height. This detritus 

 ferments when left to itself, and a gentle heat is 

 developed in the centre of the edifice. The Cathe- 

 turus returns to lay near this coarse shelter ; it then 

 take^ each egg and buries it in the heap, the larger 

 end uppermost. It places a new layer above, and 

 quits its labour for good. Incubation takes place 

 favoured by the uniform heat of this decomposing 



' Brehm, Edition Fran^aise, Crustacis, p. 738. 



