FALCONID^ — THE FALCONS. 109 



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

 immaculate. 



Wing, 13.65 - 16.00 ; tail, 8.40-9.50 ; 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. Hub. Central and Eastern Europe, Western 



Asia, and adjoining portions of Africa .... \?iV. lanarins} 



h. 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.C0 - 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 . . vixr. p oly agrtia. 

 Wing, 11.50; tail, 6.60; culmen, .70; tarsus, 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. Bah. Mexico . . . \ar. mexican us. ^ 



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. Hub. Southern Asia. 



var. jucjger? 



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

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

 upper part of the tarsus ; 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 sliglit specific differences are illustrated by the figures on 

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

 extends through a great range of latitude, as, for instance, the Pcdioccetes 

 phasianellus, the northern race of which has the feathers covering the base of 

 the toes so long as to reach beyond the claws and nearly conceal them, while 

 in the southern form (var. coliimbiaivus) the toes are almost completely naked. 



My determination of the number and character of the geographical races 

 of i^. gijrfalco is the result of a very careful critical- examination of over sixty 



1 Falco lanarius, var. Icmarins (Schlegel). Fcdco lanarius, Schleg. Krit. Ueb. II, et 11. — Ib. 

 Tr. Fauc. 6 ; Mus. Paj-s-Bas, Falconcs li ; Abli. Zool. 16 ; Rev. 1844, 2 ; Naum. 1855, 252 ; Ibis, 

 1859, 86. — Bree, B. Eur. I, 1859, 37 (plate of adult !). — Tristram, Ibis, 284. — Gr.ay, Hand 

 List, I, 1869, 19, No. 171. Pelz. Ueb. der Geier und Falk. *I1, 1863, 20. Falco lanarius a, 

 Schleg. Tr. Fauc. 23. Gennaia lanarius, Schleg. — Bonap. Eev. 1854, 535. Falco feldeggii, 

 Schleg. Abh. Zool. 3-6. 



^ Falco lanarius, var. mexicanus (Light.). Falco mexicaims, " Light. Mus. Berol." — 

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

 der Geieruud Falk. II, 1863, 19. " Falco sublaiiarius, Natterer." — Pelz. Ueb. der Geier und 

 Falk. II, 1863, 19. 



^ Falco lanarius, var. jugger (Gray). Falco jugger, Gray, Hardw. 111. lud. Zool. II, pi. xxvi, 

 1832. — Bonap. Consp. 2^. —Gould, B. Asia, pi. i. — Jerdon, B. India, 30. — Strickl. Orn. 

 Syn. 1855, 79, No. 129. — Schleg. Abh. pi. .xv; Mus. Pays-Bas. I, 17. Falco lugger, Jerd. 

 Aladr. Jourii. X, p. 80; 111. Ind. Orn. pi. xliv. — Blyth, Journ. Ass. Soc. Bengal, XI, 104. 

 Falco thcnnophilus, Hodgs. Zool. Misc. 1844, 81. Falco lanarius? Blyth, J. As. Soc. Beng. 

 XIX, 318. 



