Page 466. 
170 THE CAROTID ARTERIES OF BIRDS. 
CAPITONIDA. 
The left carotid only is present in these birds. 
Species examined. 
Megalema asiatica. Indicator major. 
Barbatula duchaillu. 
PSITTACI. 
The Parrots are peculiar for the variation that occurs in their caro- 
tids, which show four different arrangements: first, there may be two 
in the normal position; secondly, the right may, as it usually does, 
traverse the hypapophysial canal, whilst the left, in a manner quite 
exceptional, runs superficially along the side of the neck in company 
with the left pneumogastric nerve and the left jugular vein; thirdly, 
the right may be very small, and blend with the much larger normally 
situated left (in Cacatua sulphurea, according to Meckel) ; and fourthly, 
the left may alone be developed, as in the Passeres. The first of these 
four conditions is only found in Old-World Parrots; and the last two 
are restricted to the Cacatuine. 
Species examined. 
In the following species the first plan prevails, the two carotids 
running normally :— 
Stringops habroptilus. Prioniturus, sp. 
Calopsitta nove-hollandice. Hos cardinalis. 
Eolophus (Cacatua) roseicapillus. indica. 
Euphema pulchella. Trichoglossus concinnus. 
splendida. Loriculus, sp. 
bourkit. Aprosmictus scapulatus. 
Melopsittacus undulatus. Paleornis alexandri. 
Agapornis roseicollis. 
The following species belong to the second division, the right 
carotid running normally, whilst the left runs up the side of the neck, 
together with the left pneumogastric nerve and jugular vein :— 
Ara macao. Nestor notabilis. 
Conurus cruentatus. hypopolius. 
wantholeemus. Brotogerys tiriacula. 
jendaya. ——— virescens. 
petit. tui. 
holochlorus. Pionus menstruus. 
Caica melanocephala. Chrysotis festiva. 
Psitiacus erithacus. ochrocephala. 
