1870. ] LETTER FROM MR. W. H. HUDSON. 159 
quently a ‘ Woodpecker which never climbs a tree’ (Origin of Species, 
4th ed. ch. vi. pp. 212, 213). 
“The perusal of the passage quoted by one acquainted with the 
bird referred to and its habits might induce him to believe that the 
author had purposely wrested the truth in order to prove his theory ; 
but as Mr. Darwin’s ‘ Researches’ were written long before the theory 
of natural selection was conceived, and abound in similar misstate- 
ments when treating of this country, the error must be attributed to 
other causes. The facts are, that besides orchards, and groves of 
willow, poplar, &c., which have been planted wherever the plains are 
settled, there is also the continuous wood, which I have already de- 
scribed, growing on the shores of the La Plata. 
** South of Salado River the numbers of wild trees have given a 
name to a large department of this province. There is also in the 
vicinity of Dolores, 150 miles south of Buenos Ayres city, a very 
extensive forest. All these wouds are frequented by the Carpintero, 
where he may be observed climbing the trees, resting on his stiff 
and frayed tail-feathers, and boring the bark with his bill as other 
Woodpeckers do. But his favourite resort is to the solitary Omdbu, 
a tree found over a great extent of the plains of Buenos Ayres. 
This tree attains a considerable size; there is one situated within 
fifty paces of the room I am writing in that has a trunk which 
measures at a height of 3 feet above the ground 30 feet in circum- 
ference. This very tree was for years a breeding-place for several 
Carpinteros, and still exhibits on its trunk and larger branches scars 
of old wounds inflicted by their bills. The wood of the Ombu is 
very soft; and the Carpintero invariably bores for breeding where 
it is green and sound. The hole it forms runs horizontally about 
9 inches into the tree, then slants upward a few inches more, and at 
the end of this passage a round chamber is excavated to receive the 
eggs. 
a The Carpintero frequently lights on the ground, where it is 
seen to feed on ants and larvee, and is sometimes found several miles 
distant from any trees. This, however, is very rare; and it is on 
such occasions always apparently on its way to some tree or trees in 
the distance. It very rarely takes a long flight, but travels by very 
easy stages. These circumstances have led to its being described as 
living exclusively on the ground. Outlying the regions abounding 
in trees, and which I have described as the habitat of the Carpintero, 
there are vast tracts in the southern and western portions of Buenos 
Ayres where, in truth, ‘not a tree grows;’ but in these regions the 
Carpintero is never seen. It is not only the erroneous account of 
this bird’s habits that makes Mr. Darwin’s mention of it peculiarly 
unfortunate, but also because this bird rather affords an argument 
against the truth of Mr. Darwin’s hypothesis. Mr. Darwin describes 
it as a perfect Woodpecker, not only in conformation, but in its eo- 
louring, undulatory flight, and shrill obstreperous cries. It is plain, 
then, that natural selection has left it unaltered; and is it not rea- 
sonable to suppose that, if there was such an agency in nature, it 
would have done something to alter this species, placed as it is in a 
