AORTA—ARGUS 21 
reality but few of these birds have an outward resemblance to Shrikes, 
Thrushes, or Wrens, and all belong to quite a different division of 
PASSERES. In 1847 Johannes Miiller and Prof. Cabanis justly 
placed them among their CLAMATORES, and subsequently Garrod 
shewed their Mesomyodian structure. The Formicariide are one 
of the most characteristic Families of the Neotropical Region, 
abounding in the forest-districts of its middle portion, becoming 
less numerous in Central America, and still scarcer in the southern 
parts, only just reaching the plains of La Plata. They are mostly 
small birds of sober hue, some not bigger than Wrens ; but members 
of the Genera Batara and Grallaria attain the stature of a Jay. The 
last named of them has much the appearance of a PrITTA—a distinct 
group to which the name “Ant-Thrush” has also been applied. 
As is the case with most South-American birds, scarcely anything is 
known of their habits. The large genus Thammnophilus, containing 
upwards of 50 species, is one of the most 
important of the so-called ‘‘ Bush-Shrikes,” 
and many of its members are remarkable 
for the sexual diversity in plumage, that 
of the cocks being black or black banded 
with white, while that of the hens is 
rufous; but in some other groups the 
black or black-and-white plumage is ee 
: Ant-THrusH (Thannophilus). 
common to both sexes. Of this genus (Adean'S wainaon.) 
several species inhabit British Guiana, at 
least three occur in Trinidad, and one is found in Tobago, where it 
is known as the Qua-qua or Cata-bird (Ann. N. H. xx. p. 331), their 
presence in these two islands offering one of the many strong 
proofs of their fauna belonging to that of continental South 
America, since no member of the Family is found in the Antilles 
proper. 
AORTA (adj. aortic), the principal ARTERY from which arise 
the blood-vessels. supplying the trunk, hind limbs, and viscera below 
or behind the heart (see VASCULAR SYSTEM). 
APTERYX, see KIw1. 
ARCH AOPTERYX, see Fosstt Birps. 
AREND, the Dutch for Eagle, but used by the colonists in 
South Africa for the Bearded Vulture or LAMMERGEYER. 
ARGALA, Hindoo Hargila—said by Yule to be the xia of 
Mlian (xvi. 4)—a name of the ADJUTANT. 
ARGUS or ARGUS-PHEASANT, the name originally applied 
in ornithology to the extraordinary and beautiful birds of the 
Malay Peninsula, Siam, and Borneo, which are not distantly related 
to the Pracock; but by English sportsmen in India commonly 
