xviii LIST OF ILLUSTRATIONS 
FIG, 
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2i. 
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290. 
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PAGE 
DIAGRAM ILLUSTRATING CIRCULATION OF BLOOD. .. 70 
(a) Birp’s Hrart, (4) HUMAN HEART, OPENED TO SHOW 
VALVES... . ds Aric die Yen Be woe we & 993 
(2) AND (4) RED AND Wate eoveiacies OF Mav, (c) 
AND (@) RED CoRPUSCLES OF HUMMING BIRD AND 
OsTRICH, (e) AMEBE «1 1 ee ee ee eS 
AIR-SACKS—DIAGRAM . dey | deceetaoer te ext HE 80 
SECTION OF (2) FEMUR OF OSTRICH, (4) OF SKULL OF 
CARINATE BIRD... 1... a ‘ 82 
DiapHraGM oF Duck . «1. 1 wee. 8S 
DIAGRAM ILLUSTRATING PROCESS OF BREATHING. . 87 
Do. DO. DO. es cual OT 
HuMERus oF (¢) Sxua, (6) HORNBILL, (c) EAGLE . . Ir 
Two CuBEs eae ee 113 
BRAIN OF BirD — a eset A oy wae 4 = 218 
EYE oF (a) Man, (4) TyPicaL Birp, () Ginn ee ee a 
SECTION OF RETINA OF BirD os wee 125 
(a) HuMAN Ear, (6) Ear oF OWL, (c) OF reaver en 132 
SyRINX OF RAVEN... 0. ew ee 
CONVOLUTIONS OF CRANE’S TRACHEA. ......., 140 
STRIATED AND UNSTRIATED MUSCLE ee ee 2 
(@) FEATHER CARRYING NESTLING DOWN-FEATHER, (6) 
NESTLING ‘‘DOWN” OF THRUSH, (c) OF PiGEON, (d) 
THREAD FEATHER : ar elgg + 145 
ConTOUR FEATHERS, (a) PLUMELIKE, (6) FLIGHT-FEATHER 147 
BARBULES AND BARBICELS TO ILLUSTRATE INTERLOCK- 
ING 05 EE ER RR alee ee, a 98 
CassowaRy’S FEATHER .......,., eae 150 
ILLUSTRATION OF DEVELOPMENT OF FEATHER . I5t 
Brak OF (1) Fatcon, (2) Duck... ..., 162 
Foor oF (1) WOODPECKER, (2) GREBE. . , . - . 168 
FLExor TENDONS OF TOES oF (2) Fow1, (4) Pctine 
a eo re 
