76 THE POPULAR SCIENCE MONTHLY. 



feathers; the autumnal molt being the only complete process, 

 while the spring change is effected simply by the " casting " off 

 of the broken points of feathers in the worn plumage. The 

 young of all the thrushes are spotted in their nestling dress, but 

 never carry it beyond the first autumn, assuming the full plum- 

 age of the old birds after the tirst molt, so that " a bird of the 

 year" in the late fall and winter is scarcely distinguishable 

 from its parents. Any one who is familiar with the young rob- 

 ins hopping about the lawn in the early summer, with their 

 spotted breasts and mottled backs, may have wondered what 

 became of them by October. 



The thrushes are migratory birds in the temperate zone, as 

 the nature of their food demands, partaking in the general north 

 and south movement during the spring and fall tides of migra- 

 tion. Though not strictly gregarious, many of the species asso- 

 ciate in loose flocks, on the approach of autumn, and forage 

 over the country in quest of food. We are all familiar with the 

 flocks of robins in the fall, scattering overhead, or in the gum- 

 trees feasting on the ripe, black fruit. They are for the most 

 part arboreal, living largely among the trees, but some of the 



species build nests on the ground, 

 or in the undergrowth just above 

 it, and all of them frequent the 

 ground at times when food is to 

 be obtained there. Being among 

 the most highly organized of 

 birds, the thrushes are conse- 

 quently rapid livers, possessing a 

 high degree of vitality, and con- 

 suming a very large proportion 

 of oxygen. Great feeders, strong 

 of wing and stout of heart, with 

 RoBiN-REBBBEAST. ^^rm, fast - flowiug blood and 



high temperature, they are, in 

 every sense of the word, alive to their environment. 



The robin and his world-wide congeners form the genus 

 Turdus, or true thrushes, comprising upward of fifty well-de- 

 fined species distributed throughout the forest regions of the 

 globe, excepting Australia and New Zealand, where they are 

 replaced by an allied group. 



In the palsearctic region of the Old World four widely dis- 

 tributed species occur, all having spotted breasts in the adult 

 plumage. The red-winged thrush breeds in the birch region, 

 and throughout the upper belt of pines across Europe and Asia, 

 from the Atlantic to the Pacific. He is rare east of the valley 

 of the Yenisei, but extends his wanderings northward as far as 



