FALCONID.E — THE FALCONS. 109 



secondaries without distinct spots on tlie outer webs. Lower tail-coverts 

 inniiaculate. 



Wing, 13.65 - IG.OO ; tail, 8.40-0.50 ; culmen, .85 - 1.00 ; tarsus, 1.95 - 

 2.15; middle toe, 1.85-1.95. Top of the head white, with narrow- 

 streaks of dark brown. Ilab. Central and Eastern Europe, We.stern 

 Asia, and adjoining portions of Africa .... var. lanariuf:} 

 b. Outer webs of tail-feathers without distinct light spots, or without any at 

 all; outer webs of primaries with no trace of spots; secondaries with light 

 spots on outer webs. Lower tail-coverts sparsely spotted. 



Wing, 12.00 - 14.25 ; tail, 7.60-9.00 ; culmen, .75 -.90; tarsus, 2.15- 

 2.40; middle toe, 1.70-2.00. Top of head brown, with narrow black 

 streaks. Adult. Above with obscure transverse spots of bluish. 

 Young. Above with feathers bordered with rusty . . \m\ p oly agr ua. 

 Wing, 11.50; tail, 6.60; culmen, .70; tarsu.s, 1.90; middle toe, 1.65. 

 Above uniform dark brown, with a faint plumbeous cast, the feathers 

 without trace of light or rusty edges; outer web of tail-feathers with- 

 out trace of light spots. Hah. Me.xico . . . var. mexicanu.i.' 

 Wing, 13.60-14.30; tail, 8.25-9.00; culmen, .80 -.87; tarsus, 1.85 - 

 1.90 ; middle toe, 1.85 - 1.90. Colors similar to the last ; entire auricu- 

 lars white ; mustache narrow and conspicuous. Hah. Southern Asia. 



var. j u grj er .' 



The only iDoiiit of difference in tlie external anatomy between the Lanner 

 Falcons and Gerfalcons consists in the different degree of feathering on the 

 upper part of the tarstts ; this is much denser and extends farther down 

 and more around the posterior face in the Gerfalcons, but they, being inhab- 

 itants of a very northern latitude, need this protection against the rigor of 

 the climate. These slight specific differences are illustrated by the figures on 

 page 1430. The same difference is observable in many birds whose habitat 

 extends througli a great range of latitude, as, for instance, tlie Pcdioccetes 

 phasianeUus, the nortliern race of whicli has the feathers covering the base of 

 the toes so long as to reach beyond the claws and nearly conceal them, vN'hile 

 in the so ithern form (v;ir. cohunhianiis) tlie toes are almost completely naked. 



My determination of tlie number and character of the geographical races 

 of F. (jijrfako is the result of a very careful critical examinulion of over sixty 



' Falco lanarius, var. lanarius (Schlegel). Falco Innarius, Schleg. Kiit. Ueh. 11, et 11. — Ib. 

 Tr. Fauo. 6 ; Mus. Pays-Bas, Falconen 14 ; Abh. Zool. IG ; Rev. 1844, 2 ; Nauni. 1855, 252 ; Ibi.s, 

 1850, 86. — BriEE, B. Eur. I, 1859, 37 (plate of adult !). — TnisTitAM, Ibis, 284. —Quay, Hand 

 List, I, 1869, 19, No. 171. Pelz. Ueb. der Geier und Falk. II, 1863, 20. Falco lanarius a, 

 ScHLEH. Tr. Faue. 23. Gcnimia lanarius, Schleg. — Bonap. Rev. 1854, 535. Falco fcldcgijii, 

 SciiLEG. Abh. Zool. 3-6. 



^ Fa'co lanarius, var. mcxicn.nwi (Licht.). Falro mcxicanus, " Licni. Mus. Bcrol." — 

 .Schleg. Abh. Zool. 1841, 15. — Schleg. Falconcs, Mus. Pays-Bas, 1862, 18. — Pelz. Neb. 

 der Geierund Falk. II, 1863, 19. "Falco suhlanarius, N.iTTEi'.Er.." — Pelz. Ueb. der Geier und 

 Falk. II, 1863, 19. 



^ Falco laiutrius, var. juggcr (tJii.w). Falco juggcr. Gray, Hardw. 111. Ind. Zool. II, pi. -x.wi, 

 1832. — BoxAP. Consp. 24. — Gould, B. Asia, jd. i. — jEr.noN, B. Indio, 30. — Stuickl. Orn. 

 Syn. 1855, 79, No. 129. — Schleg. Abh. pi. .\v; Mus. Pays-Ba.s. I, 17. Falco lunger, Jekd. 

 Aladr. Jouni. X, p. 80; 111. Ind. Oni. pi. xliv. — Blyth, Journ. -Ass. Soc. Bengal, XI, 104. 

 Falco flirrmophilus, Hones. Zool. Mise. 1844, 81. Falco lanarius' Blvtu, J. As. Soc. Beiig. 

 XIX, 318. 



