AMERICAN WARBLERS. 73 



American War1)lers fly more swiftly than tlie Blue Yellow- 

 backs, and few are more active; it is partly by this very ac- 

 tivity, as these plump little Avarlilers ho]) quickly from twi<>' 

 to twig-, that they may be recognized. AVhile, as a rule, these- 

 warblers appear to prefer deciduous trees in which to feed, 

 they are often found in pines. This is especially true in re- 

 gard to the birds of this S]3ecies which spend the summer on 

 Cape Cod, where they are abundant, and where a considerable 

 portion of the woodlands is made up of pitch pines. Yet, 

 even here, the Blue YelloAv-backs show a marked preference 

 for other kinds of woods, and when they do feed among the 

 jiines it is only on the outermost trees. They are, however 

 remarkal)ly fond of the white cedar swamps that are so com- 

 mon on the Cape, and are always found in them. 



Breeding Habits. Although I found the Blue Yel- 

 low-backs breeding at Williamsport, Pennsylvania, May 27, 

 1876 (this was possibly the southern sub-species), I do not 

 think they begin to breed in Massachusetts until the last of 

 June, and that the eggs are not deposited until the first and 

 second weeks in Jnl}^; at least, this has been my experience 

 with the species. This statement is based upon observations 

 made through a number of summers at my place in Barnsta- 

 ble. Here the birds more often choose cedar ti-ees in which 

 to build than any other kinds, and I have found quite a niim- 

 hev of nests in them. Most of these nests w ere i)laced in red 

 cedars, but I have seen some in white cedars. 



As is well known, both of these trees, in common with ma- 

 ny other species which grow on the Cape, are often so covered 

 with the lichen, called the old man's beard, that they appear 

 gray Avhen seen a little distance away. As those jjortions of 

 the trees on which the lichen grows the thickest are the ones 

 usually selected by the birds in which to build, the nests, be- 

 ing composed, at least outwardly, wholly of the gray lichen, 

 are very difficult to see. The best way to find them is to 



