2 PROCEEDINGS OF THE NATIONAL MUSEUM vol.80 



the young birds when emerging from the egg are in the first pen- 

 naceous, or juvenal, plumage. Pycraft^ has noted this, but his 

 paper has been largely overlooked by ornithologists. 



The embryo has the following dimensions, in millimeters (the sizes 

 of the culmen and wings are included as a scale by which to compare 

 the embryo, the chicks, and the adults): Culmen, 11; wing, 74; 

 tarsus, 28; first toe (without claw), 16; claw, 8; second toe, 1G.5; 

 claM^, 8 ; third toe, 14.5 ; claw, 8 ; fourth toe, 11 ; claw, 7.5. 



The two chicks are alike in their dimensions (millimeters) : Cul- 

 men, 11 ; wing, 82 ; tarsus, 28 ; first toe, 16 ; claw, 8.5 ; second toe, 17 ; 

 claw, 8.5 ; third toe, 15 ; claw, 8.5 ; fourth toe, 11 ; claw, 8. 



Adults vary as follows (millimeters) : Culmen, 22-26 (average, 

 24); wing, 178-192 (185); tarsus, 56-60 (58); first toe, 30; claw, 

 18 ; second toe, 31.5 ; claw, 19 ; third toe, 30 ; ciaw, 18 ; fourth toe, 23 ; 

 claw, 18.5. 



To summarize these data : The wing increases from 82 to 185 mm., 

 an increase of approximately 126 per cent ; the culmen grovv's from 11 

 to 24 mm., an increase of 118 per cent; the tarsus increases from 28 

 to 58 mm., a growth of 107 per cent ; the first toe from 16 to 30 mm., 

 an increase of 87.5 per cent; claw from 8 to 18 mm., an increase of 

 125 per cent; second toe from 16.5 to 31.5 mm., an increase of 91 per 

 cent; claw from 8 to 19 mm., an increase of 137.5 per cent; third 

 toe from 14.6 to 30 mm., an increase of 107 per cent ; claw from 8 to 

 18 mm., an increase of 125 per cent; fourth toe from 11 to 23 mm.,* an 

 increase of 109 per cent ; claw from 7.5 to 18.5 mm., an increase of 

 147 per cent. 



As a matter of comparison, chicks and adults of Gallus sonnerati, 

 as an example of the pheasants, and of Tinamus rohustus, as a repre- 

 sentative of the tiuamous (two fairly related groups), were examined, 

 with the following results: In Gallus sonnerati, the culmen was 

 found to increase by 56 per cent ; the wings of the young chicks being 

 unfortunately in poor condition, the wing growth could not be esti- 

 mated; the tarsus increased by 114 per cent; the first toe by 26 per 

 cent; the second toe by 37 per cent; the third toe by 32.5 per cent; 

 the fourth toe by 13 per cent; the claws by 10 to 25 per cent. In 

 Tinamus rohustus again no wing data could be obtained; the culmen 

 increased by 130 per cent; the tarsus by 129 per cent; the first toe 

 by 95 jDer cent ; the second toe by 85 per cent ; the third toe by 85 per 

 cent; the fourth toe by only 35 per cent. The claws increased by 

 about 300 per cent. 



On looking over these figures we may note that the megapodes show 

 a much greater postnatal development of the claws than Gallus and 

 much less than Tinamus; they show a greater growth of the toes 



iProc. Fourth Internat. Ornith. Congr., p. 458, 1907. 



