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 58 THE CONDOR VOL. XII the nest of the bird and that of the insects may often be found within three or four feet of each other. The protection, however, is not always so complete. A curi- ous variation of the situation occurs when a tree with leaves closely resembling those of the acacia is selected, and the nest is placed beside that of a species of ant, which at first sight would probably be mistaken for a homeifs nest, so similar are the two in appearance. (See Fig. 18.) The nest of the Beardless Flycatcher, Camplostoma mberbe, is built in a small species of palmetto, in the upper angle formed by the juncture of a leaf-stem with the trunk. The trunk is very shaggy with the frayed margins of the fibrous sheaths, and the nest can be reacht without difficulty by any climbing animal. The danger from such enemies, however, is greatly reduced by the structure and material of the nest. Except for the soft cottony lining it is composed entirely of fibers obtained from the trunk of the palm, which are deftly interwoven with those fringing the sheaths, so that one might easily mistake the whole structure for a mere tangled tuft of loosened fibers. The small hole at the side by which the cav- ity is entered is turned directly away from the trunk and would not be likely to attract the notice of any reptile climbing it. Many other instances might be cited of similar adaptations in nests of this class, as in the case of the wood wrens, ]heuopedius, the Passefine genus Artcroon, the Cotongine genus ]achyramphus, a small Rail, Creciscus tuber, etc. but further illustrations are unnecessary. Most of the protective adaptations thus far considered are characteristic of species inhabiting foregts or dense thickets, where the principal enemies to be guarded against are reptiles or small mammals. In the more open sections of British Honduras, known as pine ridges--flat, grassy tracts with a scant sprinkling of low pines--the case is quite different. Here the chief enemies are jays, especial- ly ]silorh[nus, hawks and probably vultures. Several of the common species in- habitingthese localities have adopted a means of protection eminently suited to their circumstances. In studying the nesting habits o the bird fauna of the pine ridges, one of the first phenomena noticed is the tendency of several species to nest in close proximity to each other. The colonies thus established are composed of widely separated forms, mostly tanagers and flycatchers, which may be found nest- ing peacefully within a few yards of each other. If a number of the colonies are examined it will invariably be found that the nests of the other species are grouped about that of the splendid Derby Flycatcher, )itanus. This bird is one of the most powerful and warlike, as it is one of the handsomest of the great Tyrannine group. It is never known, however, to molest weaker species, permitting them to make their nests undisturbed within a few yards of its own. Doubtless the courage and "magnanimity" of this species have caused it to be- come the unconscious protector of its weaker neighbors. The most common of these are the two tanagers, Tanagora abbas and T. cana and the flycatchers, Affyiozeletes sireills, Legatus albicollis, ]laenia martinica subpagana, and even the large but weak and sluggisl 3rearynchus. It is worthy of note that those forms that gather about ]itanus to nest are such as would be most likely to be- come the victims of hawks, jays, etc., both on account of their weakness and the exposure and conspicuousness of their nests. Many of the common pine ridge forms, for example, Tyrannus melancholicus, and species of 3[yiarchus, do not regularly associate themselves with these little communities, for the obvious reason that a strong and pugnacious species like T. melancholicus is amply able to de- fend its own, while those that nest in cavities of trees, like 3ryiarchus are beyond the reach of most of the common enemies. Whenever he location of one of these