The social weaver is the most advanced apartment builder. It, like the palm chat, has little of distinction in its appearance, being mostly dull brownish with a black face. But in its home country, the savannas of Rhodesia in southeastern Africa, its huge community nests in the savanna trees may be seen from afar. The largest Friedmann saw when he was studying the bird there was about 25 feet by 15 feet, by 5 feet high, and contained about 95 nests. And this might have been still bigger, for part of it had broken the branch on which it rested and fallen to the ground. Sir Andrew Smith, the early ornithologist of South Africa, has written that when these birds start a colony they first of all make a roof of coarse grass. The group to which the social weaver belongs gets its name from the remarkable ability some of them have of weaving their nesting materials. But the social weaver neither plaits nor weaves its roof. It puts the roof together in the form of a well-made hayrick with a fairly definite thatching arrangement so that the water runs off. This is a community effort. Under this roof each individual pair makes its own separate nest. These apartment houses are used year after year, but last year's chambers are not used, new ones being made under the roof each year, and so it grows bigger and bigger until the weight of the mass may break the branches and cause a part or the whole to fall to the ground. BIRD HELPERS AT NESTING TIME [Illustration] In many a well-run American home the children have definite responsibilities, the older children may help look after the younger, and even grown-up relatives may stay as part of the family group. As in so many cases there may be found parallels to this in the bird world. The ani, the curious tropical American cuckoo that makes communal nests, is gregarious and the young of the first brood become part of the parent flock. Two more broods may be raised during one season in Cuba, and the young of the earlier brood may feed their younger brothers and sisters of the later brood. The same has been recorded for many other species in the wild: in eastern bluebirds, mountain bluebirds, wheatears, long-tailed titmice, barn swallows, coots, rails, and gallinules young have been recorded as feeding still younger birds. In captivity this habit has been seen a number of times. Young birds hardly able to feed themselves may help feed still younger individuals of the same or other species, and a nestling crowned hornbill has been seen to offer food to its nestmates. This tendency to feed nestmates evidently appears very early in the life of the bird, as Dr. C. O. Whitman, who worked intensively with pigeons at the University of Chicago, recorded a hybrid dove only twelve days old that fed its nestmate.