Jeffries oh the Primaries of Birds. l6l 



ten coverts. The same number is found in the young, though the 

 first covert is very small. 



Anisodactyltv. I have not been able to examine any young 

 of this group, which it is especially desirable to do. since in the 

 Kingfishers the adult has ten primaries, ten coverts, and a " little 

 feather," which may be another primary. This at least is the 

 case in Ceryle alcyon and in species of Dacelo. 



Pici. In Picoides arcticus the young gives the following 

 formula: Pr., 10, pr. c. 9. 3rd row. 6. In the nestlings of this 

 species and of Colaptes auratus, the only young Woodpeckers 

 I have seen, the last three or four primaries are very small and 

 seem not to become fully grown till after the moult. This may 

 be an adaptation to the home of the young bird, since it enables 

 the wing to fold up close with less pressure on the growing 

 feathers than would be the case if they were all fally developed. 



Accipitres. Among the Hawks. I have examined the young 

 of Butco pennsylvanicus and found, to my surprise, eleven prima- 

 ries, ten coverts, and a terminal claw. That it was a true claw 

 there can be no doubt, its resemblance to the undoubted claw of 

 the I finger or thumb being complete. The presence of the claw 

 is hereof interest, as it points to the existence of a third phalanx, 

 a thing not accredited to the Hawks and not ossified in my skele- 

 ton of the Sharp-shinned Hawk (Accipitcr fttsctis) . I limit my 

 remarks to this specimen, since, judging from the almost univer- 

 sal absence of the ungual phalanx of the thumb, no reliance can 

 be placed on museum specimens. In adult Buteones there is a 

 small feather in the proper position for the first primary, but 

 structurally it is onlv a contour feather. This may be developed 

 from the first primary papilla or the papilla may abort ; it is 

 difficult to say which. 



Of the remaining groups of birds my observations have been 

 even more sparse than in the foregoing. For convenience I will 

 next consider the Ducks, taking a domestic Duck in illustration. 

 In this case, as is true of all the lower birds, down tufts are 

 developed from the papilla' of the primaries, thus making a 

 strong contrast to the young birds previously described, where 

 the papillae assume the structure of pin-feathers before they burst. 

 So instead of simply counting the papilla- we must separate out 

 the. little tufts and count their number. If this is done in the 

 case of a young Duck eleven primary tufts and ten smaller covert 



