feathers of the free, well nourished road-runner, Rhody. But they do appear in the tail feathers of the confined thrashers Okii and Chiisai: on their first tail feathers even before they were fully grown at a time when they were being hand fed and therefore, because of the artificial character of the food and perhaps also because of the absence of their parents' saliva in that food, were probably improperly nourished. (Fully grown, above, refers to the feathers primarily, although the birds also were, of course, not full-grown). Further, these young thrashers, now broken in to artificial food and apparently well and vigorous, are now getting their second sets of tail feathers. Hunger-marks on these new feathers are few. Again, Archie and Terry, taken from the nest and hand reared showed many hunger marks on their first tail feathers, but there were few on their second while still in captivity. These hunger-marks, as I see them, are narrow grooves, probably V-shaped as Pycraft says, and in them there is apparently an absence of continuity of the barbs; the barbs appear as if broken or much thinned. (I have not examined them with a good glass). The light shines through the vane at these marks, and the vane may break along them. They do not necessarily appear in worn feathers, as shown above. I did not find them in Brownie's, although I ob- erved many of his moults. He was a free, well-nourished bird. Examination of the road-runner skins in the M.V.Z., I believe, will disclose that the majority of the tail feathers, by far, do not have them. They do, however, appear in the sprouting, first, rectrices of fledglings taken from the nest and reared by hand; perfectly fresh, uninjured feathers. They appear to be formed during the process of growth and not as the result of injury from extraneous causes. Nor, based on my own limited experience alone, does it ap- pear that, what I call a hunger-mark, results from wear on a water- mark. However, I can see that, where there is defective nutrition, a hunger-mark may be but an exaggerated water-mark, or more pro- perly; the effect of the same cause that accounts for water-marks, but a cause that, so to speak, has gone out of control. All this, however, while the feather is growing--not after it has ceased to grow and has been subjected to wear. Now, if I understand Grinnell correctly, the things he calls water-marks are the result of discontinuous growth of the feather: there are alternating periods of rapid and slow growth. These leave marks on the feathers. (Somewhat analogous to the rings of trees, though he did not say so). Now does it not seem reasonable that, if the bird is suffering from mal-nutrition, growth during the "slow" period may of such defective character as to leave actual physical, visible lines of weakness in the feather structure? That is, hunger-marks. (No doubt this is all covered in the literature, of which I have read none, except the one article above referred to, which merely mentions the matter). [illegible] (At this point in writing the above I went out to have a close look at the two young thrashers, Okii and Chiisai. I found that, on the original rectrices, Chiisai showed but few hunger marks, whereas Okii showed a great many. Now this is curious; for these notes show that, for several weeks, Chiisai was growing to maturity I had doubts of Chiisai's reaching maturity, because of his being, what aviculturists call, a "soft bird": a weakling as