10ai» ' OR. K. A. WILSON ON THK [JlUie 14' 



a gentle aiDplicHtioii of force removes them like small caps, leaving 

 the new shorter claws beneath, each marked by a groove where 

 the old claw was attached. This groove persists often for some 

 little time, and is as infallible a sign that the bird is at least 

 a year old, as the presence of the claw itself residy to drop ofl". 

 Young V)irds of the year do not shed their claws and therefore 

 never have the groove. 



Tliere is another method of determining a bird's age which i.s 

 often used as a rougli indication upcm the moor, namely, to pull 

 out the third primary-featlier of the wing at its distal end. If 

 blood can be squeezed from the quill it is considered ns a sign 

 that the bird is of the year. If no blood can be .scpieezed and the 

 feather is old and dry, it is considered as a sign that the bird is 

 more than a year old. 



This reasoning is based ujjon the following facts: — When a 

 chicken produces its first set of primnry wing-feathers they are all 

 verv thin and we:ik, and soon become frnyed out ; they have rather 

 • narrow pointed ends, and are blackish -brown, mottled with in- 

 complete buff bars. Nine of these little feathers can be counted in 

 series, and the weakest of all is the ninth counting from the distal 

 to the proximal end. The growing power, as judged by the .size ot 

 therojt-.slieath.s of these feathers, increases from the ninth dist<\lly, 

 so that at one period of growth (F) the feather No. 4 is the longest, 

 then a little later (G) No. 3, then .still later (H) No. 2. But No. 1 

 remains jiermanentl)' shorter than No. "2. 



Bv the time Nos, 1 and 2 are ap[)r()aclung full growth, the 

 weak chicken -feathers Nos. 9, 8, 7, and so on have been shed, and 

 in their place have appeared strong fe.ither-roots growing .strong 

 round-ended unifoi-m black primai-ies, instead of the weak, mottled, 

 more narrowly jiointed chicken-primaries. 



This shedding and replacement continues as far a.s No. 3 of the 

 chicken-primaries, but when No. 3 falls out Nos. 2 and 1 are 

 found to have grown into such long and strong feathers as to fall 

 into thp series of new replacement feathers, and so they remain, 

 now fully grown, but can be recognised (K) by their more pointed 

 ends having rather more of the bufl' markings on them than have 

 the remainder of the primaries just grown from No. 9' to No. 3'. 

 No. 3', moreover, being the latest of the whole .series of primaries 

 to have emerged, is for a time the shorte.st one ; and. even wiien 

 as long as No. 2, will be still the last one grown and will therefore 

 upon withdrawal produce blood at the quill end when squeezed 

 between the thumb and the finger. 



The following diagrams (text-fig. 150) .show very roughly thi.s 

 .sequence of growth in the primaries of chick and pullet. 



This sign of blood in the quill of the third primary is not an 

 infallible sign of youth, for it is evident that as, so(m as the feather 

 finishes its growth the quill becomesas hard and dry and bloodles.s 

 as all the others. The only indication will then be a .slight 

 •difference in the shape and contour of the lust two feathers as 

 indicated above. 



