details of behavior. Unfortunately these ideal conditions were disturbed by the arrival of another person and Rhody immediately sought concealment. As anticipated in connection with the hummers, dilution of the food mixture caused the birds to eat more of it, so that, at noon, there was less remaining in their vials than there has usually been at 5 P.M. Again the smaller bird had eaten more than the other, or about 7 cc. in 19 hours, of which 13½ hours were hours of the night. Correspondingly there appeared to be a decrease in the consumption of water, though it was not measured. A Vf (vinegar fly) was floated on the surface of the drinking water of each bird where it could not help being seen, early in the forenoon, but up to 2 P.M., had not been touched. At 2:15 R was not at the cage, nor was he to be seen anywhere near it, but, as I walked along a path in the orchard, I became aware of something coming up behind me rapidly--Rhody of course, really running purposefully with the clear intention of not being overlooked. I stopped and held out a huge piece of hamburger, so big that it did not seem possible for him to dispose of it in one piece. It seemed at first that he thought so too, for, after taking it with gentle ooks, he laid it down and looked at it doubtfully. However, he finally picked it up by one end and it went down as quickly as one could say "knife". Back-sunning was then next in order. January 31st. About 8:30 A.M. (bright and sunny) Rhody could be heard singing somewhere. Later Julio informed me it was near the sage at the glade, and that he wanted no mouse. I found him there at 9 sunning his back. He whined in greeting but showed no interest in food. When talked to, he muttered softly two or three times. Here appears to be an example of his greeting me with a recognition call (whine) in no way coupled with a desire for food. I now went into the cage to see R5 (also sunning his back). He greeted me with a low hroo_. He has never whined for me. I coke-coked and coo-cooed without interesting him, but Rhody, still by the sagebrush, immediately rattle-boomed sonorously. R5, who had ignored my counterfeit efforts, evidently recognized the "real goods", came quickly down from his roost, ran to the outer cage, mounted to a high perch and stared off in Rhody's direction, but made no call. Waiting 2 or 3 minutes brought no results, so I left them as they were. At 2:15 P.M. I saw Rhody at the cage watching R5. As soon as he saw me approaching, he revised his plan and came to me. We then went to the tool-house for a mouse. He followed to the door, but then changed his course to the shop-yard and watched me through the window, joining me at the door when he saw I had caught the mouse. Now followed (for the first time this season) another step in the development of his courting behavior. (Singing was the first stage, Jan.3rd) He seemed undetermined as to what to do with the mouse. Appeared to consider his next step. He now began to wag his tail sideways; then bowed and hooed. Now he needed some objective toward which to direct his next move. This proved to be the general vicinity of the cage. R5 was now in the outer portion watching interestingly. R advanced toward him slowly and hesitatingly.