i8o BIRDS OF LA PLATA 



first blow on the wood the snake flew into two 

 pieces, A mouse gives it a great deal of trouble, 

 for after it has been killed it cannot be devoured 

 until reduced by repeated blows to a soft pulp, 

 after which it is with great labour pulled to pieces 

 and eaten. Snails and Ampullaris are also pounded 

 until the shell breaks. In spring they sometimes 

 join the train of Hooded Gulls, Guira Cuckoos, 

 Cow-birds, and various other kinds which follow 

 the plough to pick up worms and larvae ; but on the 

 ground the Bienteveo is awkward in its motions, for 

 it cannot run like the Tyrant-birds of terrestrial 

 habits, but only hops. At estancia houses, when a 

 cow is slaughtered, it comes in with the fowls, 

 Carrion Hawks, and dogs, for small pickings, being 

 very fond of fresh meat. It is a common thing to 

 see a Bienteveo following a rural butcher's cart, and 

 waiting for an opportunity to dash in and carry off 

 any small piece of meat or fat it is able to detach. 

 In the autumn they feed very much on ripe fruit, 

 preferring grapes, which they can swallow whole, 

 and figs, which are soft and easily devoured. 



In its nidification the Bienteveo also departs widely 

 from the, so to speak, traditional habits of its con- 

 geners ; for whereas most Tyrants make shallow 

 nests, this species makes a very big elaborate domed 

 structure, and sometimes takes five or six weeks to 

 complete it. It is placed in a tree, without any 

 attempt at concealment, and is about a foot deep 

 and eight or nine inches broad, and composed of a 

 variety of soft materials, chiefly wool. The entrance 



