392 On the various Plumages of Buteo solitarius. 
jB. horealis calurus, whicli are dichromatic, as is also the 
American Screech-Owl; and in neither instance, so far as the 
writer is aware^ is there any cause to believe that the species 
is changing into darker or lighter forms. 
Below are appended the measurements (in inches) of 
twenty-seven specimens^ from which will be apparent at a 
glance, among other points, the constantly larger size of the 
female : — 
Males 
• 
No. 
2. 
5. 
6. 
7. 
8. 
9. 
11. 
15. 
18. 
20. 
24. 
25. 
26. 
27. 
29. 
Date. 
Wing. 
Tail. 
Tarsus. 
Bill 
with 
cere. 
Cere. 
Remarks. 
Dec. 3,1899. 
Nov. 15, „ 
June 9, „ 
Nov. 4, „ 
14 
Feb. 9, 1900. 
97 
•)} ^' } }) 
Mch. 10, „ 
Sept. 16, „ 
97 
?; -'} }) 
„ 27, „ 
Dec. 14, „ 
Apr. 10, „ 
10-00 
10-88 
10-37 
10-25 
10-18 
10-89 
10-25 
10-00 
10-12 
10-40 
10-25 
10-50 
10-95 
9-75 
10-50 
6-75 
6-75 
•00 
6-50 
6-16 
6^45 
6-50 
6-13 
675 
6-00 
7-00 
7-10 
6-00 
6-50 
6-12 
2-75 
2-45 
2-70 
2-63 
2-65 
2-69 
2 69 
2-63 
2-68 
2-75 
2-88 
2-67 
2-75 
2 65 
2-75 
115 
1-18 
1-08 
1-19 
1-19 
1-19 
1-20 
1-19 
1-19 
1-15 
1-15 
1-18 
1-13 
1-15 
]15 
■80 
•75 
•76 
•80 
•80 
•80 
•87 
•84 
•85 
•80 
•78 
•87 
•78 
•77 
■77 
Adult, light phase. 
Juv., dark phasii. 
Juv., light phase. 
Adult, dark phase. 
Adult, dark phase. 
Nearly adult, dark phase. 
Juv., dark phase. 
Adult, dark phase. 
Adult, light phase. 
Adult, dark phase. 
Adult, light phase. 
Juv. light phase. 
Adult, dark phase. 
Adult, dark phase. 
Adult, dark phase. 
Females. 
Bill 
No. 
Date 
Wing. 
Tail. 
Tarsus. 
with 
cere. 
Cere. 
Eemarks. 
1. 
Dec. 2, 
1899. 
11-25 
7-00 
2^84 
1-25 
•95 
Juv., white phase. 
3. 
9 
7> —' 
» 
11-76 
705 
2^81 
1-25 
1^00 
Adult, black phase. 
4. 
Jan. 12, 
1900. 
11^38 
7^00 
2-75 
1-25 
•95 
Adult, dark phase. 
10. 
li 9, 
jj 
11^25 
7-16 
2-81 
1-31 
-94 
Adult, white phase. 
12. 
Feb. 2, 
J) 
11-65 
7-25 
2^81 
1-33 
1-00 
Adult, white phase. 
14. 
„ 27, 
>) 
1113 
7-00 
2-81 
133 
1-00 
Adult, dark phase. 
16. 
,, 1^, 
)j 
11-54 
7-50 
2-95 
1-35 
•97 
Juv., light phase. 
17. 
» 17, 
jj 
11-27 
7-25 
3-00 
1-37! 1-07 
Adult, white phase. 
21. 
Apr. 21, 
J) 
1175 
6-90 
2-85 
1-30 
1^00 
Adult, white phase. 
22. 
Mch. 11, 
» 
11-88 
7-10 
2-95 
1-38 
1-00 
1 Juv., app. full-grown, 
( light phase. 
23. 
Aug. 18, 
V 
1113 
6-50 
2-85 
1-37 
1-00 
Juv., light phase. 
28. 
Apr. 3, 
» 
11-30 
6-75 
2-85 
1-40 
1-00 
1 Juv., dark phase ; tail 
i ) worn. 
