and "recreation", returning to it after very short absences, at present. Today the time spent in it far exceeded the time out. Neo was seen at home once or twice more and called from the honey- suckle a few times. He also was seen picking up and dropping a twig again. There is a certain dome-like mass of honeysuckle and rose on the fence which he fancied greatly before he built his first nest and I really expected him to build there. It was in or near this place that he was heard calling. May 25th. At 7:30 A.M. Rhody was in his house; Neo and N2 (recently a comparative stranger) were in their old area. At 8 A.M. Rhody had eaten his meat in the cage, was playing with the maggpies, but came to the tool-house for a mouse. The one offered (a lively fawn colored hybrid) bit me so that the blood flow- ed freely. I dropped it, startled, and Rhody gave chase, dropping it himself several times, but eventually killing it quickly and gulping it down, returning at once to his house. About 8:30 I sat near the "dome" referred to above, and listened. I could hear faint sounds. I dropped worms and Neo came out and began gathering lining material, alternately eating the worms and gathering more material. He went up into the dome and I saw him in the dusky interior sitting in what looked like an almost completed nest; but I made no close investigation. However, Neo is shabbier than ever and his stubby tail has become still more frayed. 9:30. Neo is now off calling. This is apparently the stage in nesting when the male (as so often witnessed here) seeks to secure the females acceptance of the structure as a place in which to lay eegs. As seen from the outside, the nest looks finished. Normally the thrasher (here) is satisfied with two success- ful broods in a season, but, in the event of losing one or more, continues its efforts. Neo's second attempt was a failure; so he begins a third. Now what is it that causes reproductive activities to cease when two broods are successfully reared, but to be continued when the second is a failure? In other words, what attribute of the birds' (both birds) physiological or psychologic make-up operates to restrict or extend, as the case may be, their sexual activity in accordance with the requirement that there shall be two broods per season brought from the nest? These three nests are in practically a straight line, spaced at 30 foot intervals. At 10:20 Neo was calling nearer home. I found him in a tree near the sage patch and invited him down for worms. He accepted and then moved off a few feet and began to call in short, musical phrases looking keenly in various directions, and listening. He is still at it (10:35) and there can be little doubt that he is endeavoring to get his mate to return. (Or perhaps another mate?). Rhody still in his house at the same time. At 11:30 A.M., returning from an errand, I heard a thrasher singing short songs near Rhody's old house on the west lot. I parked the car, went to the edge of the thicket, called and Neo came out for worms, still calling for his mate. As I left he was