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208 BULLETIN 133, UNITED STATES NATIONAL MUSEUM
species was fairW common on the Paraguay River above Puerto
Las Palmas on August 2. At Puerto Pinasco, Paraguay, the birds
were found in pairs along the Rio Paraguay on September 3 and
30, and Avere recorded at lagoons near Kilometer 80 on September
8, 10, and 18. On February 2, 1921, two were taken at the Paso
Alamo on the xVrroyo Sarandi north of San Vicente, Uruguay.
These birds call in a high-pitched steely rattle or a low chuck.
They are found over water where they have the habits common to
their larger relative, the ringed kingfisher, but differ from that
bird in that they are frequently found about little ponds in the
savannas, where the w^ater is shallow and small in extent.
A wounded bird exhibited a peculiarity, that I have not observed
previously, in that a small air sac, capable of distension at
will, lay underneath the skin of the lower eyelid. When this sac was
filled with air the distended lid half covered the eye, while the free
margin of the lid was pressed out until it was 2i/. mm. from the
ej^eball. The sac was rudely oval, was pointed at either end. and
extended across from inner to outer canthus. Its distension was
greater below than at the margin of the lid. The sac was distended
and deflated several times during my examination of the bird.
and the chamber was readily seen on dissection. The function of
this curious structure is evidently to protect the eye durijig impact
with water Vx'hen the bird dives.
The wing in this species is eutaxic as has been recorded by AV. D.
Miller.^'5
CHLOROCERYLE AMERICANA VIRIDIS (Vieillot)
Alccdo viridis Vieillot, Nouv. Diet. Hist. Nat., vol. 19, ISIS, p. 413.
(Paraguay.)
This form of the green kingfisher differs from C. a. americana
in larger size, and lighter green above, wliile in the female the dark
breastband is narrower and is more obscured by pale tips on the
feathers. In the areas visited the bird was found in the same locali-
ties as its larger relatives—in fact, I collected my first specimens
of all three of the species found in northern Argentina within the
space of fifteen minutes—but is less abundant. Like (J. amazona it
often frequents small pools in the savannas. At Las Palmas, Chaco,
a female was taken Jul.y 17, 1920, just after it had flown grace-
fullj'^ out to capture a passing insect on the wing. July 27 another
fished in a small estero, hovering over the water, and then darting
down to strike the water with great dasli and speed. At the Paso
Alamo on the Arro3^o Sarandi, north of San Vicente, Uruguay, a
female was taken on February 2, 1921. Another was shot near
'^«Aiik, 1920, p. 427.