228 BIRDS OF LA PLATA 
of the Rio Colorado. f differs externally in the 
more earthy hue of its plumage, which is protective 
and harmonises admirably with the colour of its 
sterile surroundings; also in having a shorter beak, 
and in being adorned with a long, slender, black crest, 
which the bird when excited carries directed for- 
wards like a horn. There is, however, an anatomical 
difference which seems to show that the two species 
are not very near relations. The structure of the 
intestinal canal in the Martineta is most peculiar, 
and unlike that of any other bird I have ever dis- 
sected: the canal divides near the stomach into a 
pair of great ducts which widen towards the middle 
and extend almost the entire length of the abdominal 
cavity, and are set with rows of large membranous 
claw-shaped protuberances. 
The Martineta inhabits the elevated table-lands, 
and is found chiefly where patches of scattered dwarf 
scrub occur among the thorny thickets. Apparently 
they do not require water, as they are met with in 
the driest situations where water never collects. 
They are extremely fond of dusting themselves, and 
form circular nest-like hollows in the ground for 
that purpose; these hollows are deep and neatly 
made, and are visited every day by the same birds 
throughout the year. They live in coveys of from 
half a dozen to twenty or thirty birds, and when 
disturbed do not as a rule take to flight at once, but 
jump up one after another and run away with amazing 
swiftness, uttering as they run shrill, squealing cries, 
as if in the greatest terror. Their flight, although 
