357b. RICHARDSON'S PIGEON HAWK. _Falco columbarius richardsoni._ Range.--Interior of North America from the Mississippi to the Rockies and from Mexico to the Saskatchewan. This species is similar to the Pigeon Hawk, but is paler both above and below, and the tail bars are more numerous and white. Their nesting habits are the same as those of the preceding species, they either building in hollow trees, or making a rude nest of sticks and twigs in the tops of trees. The eggs have a creamy ground and are sprinkled with dots and blotches of various shades of brown. Size 1.60 × 1.23. The egg figured is one of a beautiful set of four in the collection of Mr. C. W. Crandall. [Illustration 222: Brownish buff.] [Illustration: Pigeon Hawk.] [Illustration: Richardson's Pigeon Hawk.] [Illustration: left hand margin.] Page 221 358.1 MERLIN. _Falco æsalon._ This common European species was once accidentally taken in southern Greenland. Their eggs are generally laid on the ground on cliffs or banks. 359. APLOMADO FALCON. _Falco fusco-cærulescens._ Range.--Tropical America north to Mexican boundary of the United States. This handsome and strikingly marked Falcon is found in limited numbers within the United States, but south is common and widely distributed. They nest at a low elevation, in bushes or small trees, making their rude nests of twigs, lined with a few grasses. They lay three, and sometimes four, eggs which have a creamy white ground color, finely dotted with cinnamon, and with heavy blotches of brown. Size 1.75 × 1.30. 359.1. KESTREL. _Falco tinnunculus._ Range.--Whole of Europe; accidental on the coast of Massachusetts. This species is very similar in size and coloration to the American Sparrow Hawk. They are much more abundant than the Sparrow Hawk is in this country and frequently nest about houses, in hollow trees, on rafters of barns, or on ledges and embankments. Their eggs are of a reddish buff color, speckled and blotched with reddish brown, they being much darker than those of the American Sparrow Hawk. 360a. Desert Sparrow Hawk. _Falco sparverius phalæna._ Range.--Western United States from British Columbia south to Mexico. This variety is slightly larger and paler than the eastern form. There are no differences in the identification of the two varieties. [Illustration 223: Buff.] [Illustration: Aplomado Falcon. Desert Sparrow Hawk.] [Illustration: Reddish buff.] [Illustration: right hand margin.] Page 222 360. SPARROW HAWK. _Falco sparverius._ Range.--North America, east of the Rocky Mountains and north to Hudson Bay; winters from the middle portions of the United States, southward.