38 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
to ochraceous-buff; rest of under parts plain deep buff to nearly 
ochraceous-buff (or between ochraceous-buff and clay color); length 
(skins), 134-155 (147); wing, 67-71 (68.6); tail, 54-59 (56.3); culmen, 
17-20 (18.7); tarsus, 25-27 (26.1); middle toe, 15-16.5 (15.8).% 
« Hight specimens from Panam4 (mainland). 
The series examined from Panam4 comprises three adult males in dark, heavily 
barred. plumage, like the type, and ten which are more or less decidedly lighter in 
color, some of them indistinguishable, so far as I am able to see, from Colombian 
examples labeled Thamnophilus albicans. In fact, unless there are two forms of the 
species in Panam4, which is hardly probable, the individual variation in this species 
is much greater than in T. doliatus, which is reasonably constant within definite 
geographic areas. At present I have neither the material nor time necessary for 
more satisfactorily working out the problem, which, judging from the material 
examined, is a very complicated one. 
The following measurements of specimens belonging to the radiatus group are given 
below for comparison with those of Panamé examples: 
Locality. wine. | ails, | Se ae eae 
MALES. 
Thirteen adult males( T. radiatus nigricristatus) from Panamé 
Misinlarids.s. 5. +dcac sees seerersierverteds beneedekmeeeeeh erica 70.2 56.8 18.3 26.7 16.4 
Three adult males ( 7. radiatus nigricristatus?) from San Miguél 
Tsland ......--- 2-2 -eeeee ee ee eee cet ee eee ect e ence c eee een nee 73.3 57.8 18.8 26.6 16.2 
One adult male (7. radiatus nigricristatus?) from Cartagena, 
COlOMb Ia so iireciedenmcnasececwnsescietiemeenee de codenmeceaoes 70.5 57 18 27 16 
One adult male ( 7. radiatus nigricristatus?) from Santa Marta, 
COlOMDIG. cicncncncsiecmes casecnsnsses se ceeesnsamescamaisaseine 71.5 53 18.5 26 16 
Four adult males ( T. radiatus albicans?) from Bogot&, Colombia.) 75.5 61.7 19.4 26 15.8 
Six adult males ( T. radiatus subradiatus) from Upper Amazons.| 72.7 59.4 18.5 26.3 15.6 
One adult male ( 7. radiatus ?) from Lower Amazon....- 78 64 19 25.5 17 
One adult male ( 7. radiatus difficilis) from Goyaz, Brazil...... 74 64 19 27 16 
Four adult males ( 7. radiatus capistratus) from Bahia, Brazil..| 77 65 18.5 26.5 16 
Ten adult males ( 7. radiatus radiatus) from southern Brazil 
| ON Paraguay’ sccccoracieg vernsnslnve cadens teteenwslvin sa ee ais aes 74.1 63.8 17.6 26.6 15.8 
FEMALES. 
Eight adult females from Panamé (mainland).........-....... 68.6 56.3 18.7 26.1 15.8 
Five adult females from San Miguél Island..............-.---- 72.4 56.9 18.3 26.6 15.5 
One adult female from Cartagena, Colombia..............-.--. 67 52.5 18 26.5 15 
One adult female from Bonda, Santa Marta, Colombia........- 72.5 60 19.5 27.5 15.5 
One adult female from Bogot&, Colombia........-....-2-.-2+-- 73.5 59 18.5 28 16 
Three adult females from Upper Amazons.......-..-...--...-- 70.5 58.2 19.2 26.2 16.2 
One adult female from Ceara, Brazil...............--.-.---+--- 75 62 17.5 27 16 
One adult female from Goyaz, Brazil............---222-.-.-.-- 73.5 61.5 18 27 15.5 
One adult female from Bahia, Brazil...........-.... --| 72 63 17.5 23.5 14.5 
Two adult females from Chapada, Mattogrosso, Brazil......... 71.2 62.7 18 26.3 16 
