Barrows' on Birds of the Lower Uruguay. 
2 I I 
1SS3.] 
but the eggs are never visible on looking in at the orifice. The 
birds nest at about the same time as the preceding, and the eggs 
are similar but larger. 
92. Anumbius acuticaudatus Less. Espinero (Thorn- 
bird). — This well-known bird abounds at Concepcion, as it does 
almost everywhere in the Argentine Republic, where there are 
trees or bushes large enough to support its nest. The bird is not 
larger than our Wood Thrush ( Turdus must el Inns ') , but its nest 
is sometimes four feet in length, with an average diameter of two 
feet. Probably no nest as first completed would show these di- 
mensions, but as the same nest is used for several seasons in suc- 
cession its size increases until it may even exceed the above 
measurements. The bird is rather partial to thinly-wooded dis- 
tricts, and spends more of its time on the ground than do the two 
preceding species. Like them it builds its nest of twigs and 
thorns, placing it either on a tree or bush, sometimes low enough 
to be reached by the hand, sometimes at a height of twenty or 
thirty feet. The first new nest I ever examined was built in an 
ombii tree at Buenos Aires and measured about two and one-half 
feet in height by fifteen inches in diameter. 
The longer diameter was vertical and the opening at the top 
gave access to a passageway, barely large enough to admit the 
hand, and twisting regularly in a spiral to near the bottom where 
it enlarged somewhat to form the nest cavity. The spiral passage- 
way made rather more than two complete turns between orifice 
and nest, and in so doing passed between two branches of the tree 
so close together as barely to allow the passage of the bird. I 
have several times seen nests in which these passageways were 
made to pass completely around the (small) main stems of the 
trees on which they were built. In other nests the passageway, 
though never straight, was by no means a spiral, and the longer 
axis of the nest frequently becomes only slightly raised above the 
horizontal. Sometimes several nests are joined together and all 
occupied at the same time, but more often a new nest is to be 
seen built against an old one, and in the latter a Swallow or other 
bird will have built its own nest. 
Sometimes the four or five white eggs are laid on the bare, clean 
twigs of the nest; sometimes the whole interior — passage and 
nest cavity — is well lined with wool and other soft substances. 
The birds suffer much from both opossums and iguanas, the for- 
