They have not been found to be particularly quiet excepting during the hotter summer months. At other times they have been neither noticeably noisy nor silent. The outstanding features of their behavior have proven to be pugnacity and noise during the mating season and while incubating and feeding the young, and an extreme curiosity at other times. In many instances the writer has located them by utilizing this curiosity; sitting motionless on a log or rock after failing to find them, any sapsucker in the community would soon make its presence known by a characteristic interrogative call, at first from a distance, gradually drawing nearer. In winter they seem to be quite belligerent, for on several occasions one has been located by the angry noise as if of a pitched battle; on closer investigation it would be found that the sapsucker was attempting to drive some other woodpecker, generally the Gairdner, from some favorite tree. _Voice._--Bendire (1895) says: “While the nest was being rifled of its contents both parents flew about the upper limbs of the tree, uttering a number of different sounding, plaintive sounds, like ‘peeye,’ ‘pinck,’ and ‘peurr,’ some of these resembling somewhat the purring of a cat when pleased and rubbing against your leg. I used to note the different sounds in a small notebook at the very time, but scarcely ever put them down alike; each time they appeared a trifle different to the ear, and it is a hard matter to express them exactly on paper.” Mr. Dawson (Dawson and Bowles, 1909) says that while he was chopping out the nest the birds “made frequent approaches from a neighboring tree, crying _kee-a, kee-aa_, in helpless bewilderment. * * * When all was over, they raised a high, strong _qué-oo,--qeé-oo_, never before heard, and reminding one generically of the Red-headed Woodpecker of boyhood days.” SPHYRAPICUS THYROIDEUS THYROIDEUS (Cassin) WILLIAMSON’S SAPSUCKER HABITS