46 THE GROUSE IN HEALTH AND IN DISEASE 



broadly barred with bufi' and black, from the chin to the throat and neck, 

 over the breast and down the flanks, while the central lower breast and 

 abdomen are still in the autumn plumage of the previous September 

 (PI. xi. and xii.). White terminal spots may, of course, be present on 

 the breast and abdomen. These are a local or an individual character which 

 will be mentioned later in dealing with varieties of feather pattern and 

 coloration. The flank feathers of the hen in the full spring plumage show 

 much diversity of pattern. This diversity even in the same individual bird 

 Change of has l e & to the belief that the pattern may be changed in an unmoulted 

 o? 1 im- ta feather from the autumn plumage arrangement of red -brown and 

 probable. re( Jdi s h - black finely barred with lines of black to a much bolder 

 barring of buff and black. It has been surmised, from the examination of 

 single feathers, that the change commences in the centre of the feather on 

 either side of the shaft, and gradually produces another pattern of a totally 

 different colour. But can this be possible in a feather which has long been fully 

 grown, and which has presumably been long cut off from any blood or lymph 

 supply, and which is as dead as if it had been shed? (PI. xn.). It is almost 

 certain that re-arrangement of the pigment or of the pattern in this way is 

 out of the question, and the reasons for this view have already been discussed. 1 



The legs and feet of the hen Grouse in April and in May are very poorly 

 feathered, and the claws are very long (PI. xin., Figs. 3, 5). 



In June the legs and feet are almost bare, and the claws begin to drop off 

 (PI. xm., Figs. 3, 4, 5). The precise date of this shedding of the claws is 

 again really a part of the moult, and is, in consequence, equally 

 dependent upon the health of the bird. Sick birds which have sur- 

 vived the spring mortality are always late in the shedding of their claws, and 

 shedding equally late in the changing of their feathers. The claws are shed, 

 of claws. both in health and in disease, but once a year, and the casting is 

 synchronous as a rule with the disappearance of the autumn dress. The figures 

 (PI. xm.) by which this process is illustrated require but little explanation. 

 The whole of the year's growth of horny black nail becomes loose on the soft and 

 growing vascular matrix, and when quite ready to be cast can be easily pulled off 

 like a little cap. The young nail beneath is at first soft, pink and vascular 

 and very short, but soon hardens and deepens in colour, and in a month or two 

 has grown to be a useful nail of horn. The transverse or circular groove which is 



1 Vide pp. 37-40. 



