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 66 TH I If you fbllow close after them through the brush, they can be heard calling to each other with their call-note "kow kow, kow, kow" to keep the flock fairly united in its rapid march, but often- times as soon as you stop to listen to lo- cate them they are silent, save for the retreating scurry of their feet in the dead leaves and only when they are sure of their safety, will they make any real effort to gather themselves together by the use of the call note. These two examples illustrate the difference in the two types. The first, an ordinary seed-eater, is sog'ht by no one and knows it too, and often, more from surprise than real fear. he utters the first note that conres into his head, for I have frequently seen numbers of these birds glide quietly in- to their leafy shelters, leaving their comrades and mates to be surprised as they were. The quail though has learnt by experience that while there is safety in flight, still the other mem- bers of the flock must be warned of the impending danger. For all that, other species of birds have and use their dan- ger notes, only because they are rarely as emphatic, we fail to notice them and besides these species do not' need them ordinarily. For along time I thought that dan- ger or other special notes were un- known to woodpeckers and in conse- quence was greatly surprised to hear a female Gairdner woodpecker (Dr),oba/es p. airdneri) utter a special note caused by extreme fear when pursued and al- most caught by one of our smaller hawks. Another time I witnessed the death struggle of a severely wounded Califirnia woodpecker (3relanepes f. bairdi), and for some time previous to its death the bird uttered the most dis- tressing cries imaginable, which quickly drew, not one of its own species, but a ruby-crowned kinglet (le.uls calen- dttla), whose anxious actions showed how thoronghly he sympathized with the stricken woodpecker. In this in- stance the notes uttered by the latter CONDOR I Vol. IV were those of extreme distress but for all that the kinglet understood them and even hovered several times within a few feet of my head, as if to implore me to put the bird out of its agony. As an illustration of the difference between tle call-note and the danger signal of some of our smallest birds will take the notes of the California bush-tit (?sltriparus m. californicus). Why these mites of birds shoul,t use a warnin!z signal when near human be- ings, is beyond me, as they are practi- cally unmolested by them at any time, yet such is the case. Here they flit in- cessantly, in small companies, from one bush to the next over the brush-cover- ed hillsides, passing rapidly along usu- ally on a straight cotirse, completely absorbed in the search for their minute insect ood and uttering a continuous chorus of fine lisping "tsit it it tsee ee ee." Frequently I have heard them coming some distance off and have placed myself in the open, close to their line of travel in order to observe their actions better. Nearer they come un- til they are within arm's reach and their call notes still sound as merrily as .before. Suddenly one oF them recog- nizes in me something strange and un- usual. Not a move have [ made and yet first one and then another gives the xvarning note, an imperative little "tswit- tswit-tswit," and as if by magic, they pass around me and some little distance away. Not one has flowu directly away from me but for the sake of safety they have changed their course tempor- arily. In a minute or so their warning notes cease, they feel easier and their cheery little call-notes sound forth again as they resume their original di- rection through the bushes. [u this case the cause of the warning uote to- gether with its effects on the flock, were self-evident, while the utility of the call-note lies in its keeping the rapidly moving flock together. Still to conclude that the call-note of a species is needed just to keep the flock united i a big step, for in seetning contradic-