23 



brown, spotted with darker, and with a white patch over the tail, 

 from which the bird gets its name of ring-tail. The latter are 

 well-known, the male being a very large bird with the greater 

 part of its plumage of a metallic black hoe, the hen bird being 

 less than half the weight of her consort and light brown, mottled 

 with darker. 



It was pointed out that many of the birds of the same class 

 as the capercaillie exhibited great differences in the sexes, as for 

 example the domestic fowl and black game, while in others the 

 differences were scarcely perceptible, as in the case of the red 

 grouse, partridge, and quail. 



It was also pointed out that in most cases both sexes of the 

 young birds resembled the adult hen bird in plumage, but not 

 always, as e.g. the robin, in which both sexes of the young are 

 alike, both sexes of the adult bird being also alike. 



3. Ptarmigan in their spring and winter plumage and golden 

 plover in their winter, summer, and autumn plumage were ex- 

 hibited to show the different appearances assumed in different 

 seasons. The warm grey feathers of the ptarmigan in spring 

 harmonize well with the lichen-covered rocks on the tops of the 

 mountains where the birds have their home and nests. With the 

 snow comes the change to their pure white winter plumage. 



The advantage to the golden plovers of the changes that 

 they undergo in the different seasons is not so obvious. The 

 difference between the winter and autumn plumage is slight, con- 

 sisting in a greater or less golden hue in the spots on the back 

 and wings. But in the spring and summer {i.e., in the breeding 

 season) the grey colour of the breast feathers is replaced by a 

 band of deep black on a purer white ground, and the whole bird 

 assumes (in both sexes) a much more brilliant appearance. A 

 similar change occurs in or before the breeding season in the 

 males only of several species, as for example in the mallard, th^ 

 Lapland bunting, and the ruff. 



4. As examples of variation found in different localities, the 

 English sparrow was contrasted with his Spanish cousin, which 

 is altogether more brilliant, wkh brighter chestnut, deeper black, 

 and clearer white in his plumage, than ours can boast. This form 

 is separated from ours by the Pyrennees, which appears to form 

 an impassable barrier to some birds, though many species pass 

 the mountains regularly. 



On the other hand, the habitat of the hooded crow, with his 

 bluish-grey back is not separated from that of the carrion crow, 

 with his uniform sheeny-black coat, by any barrier. Though 



