Page:The British Warblers A History with Problems of Their Lives - 7 of 9.djvu/80

 about ¼" in length. A clay later the feathers are bursting and show the brown colour, the primaries being then about ½" in length; and a faint high-pitched note is uttered on the approach of the parents with food. The sixth day shows but little alteration in their appearance, but by the seventh day they become more restless, peck here and there, constantly open their bills, flap their wings, and make efforts to struggle one above the other. On the eighth day they are well feathered. On the ninth day they are very active, frequently preening their feathers, stretching their wings, and uttering their call note. Some will now be found to be stronger than others, and by more active struggling secure the topmost position. Not all of them leave the nest at the same time; the stronger are the first to scramble away amongst the undergrowth and on the ground, aided but little by their wings. At this age they are difficult to find, scattered as they are in the dense vegetation, but in a few days their wings are sufficiently strong to enable them to perch amongst the bushes, and they then sit close to one another on the same branch. Their call note is uttered frequently or even continuously during this period, but it is almost inaudible fifteen yards away. No doubt when defecation has taken place, and hunger again asserts itself, the uttering of the call note increases and enables the parents to divide their attentions equally amongst their offspring.

The vocal powers of the male are remarkably developed. In the life of the Blackcap I ventured to suggest that it was difficult to conceive of more beautiful notes being uttered than those produced by that species. However, a closer acquaintance with the vocal powers of the Marsh Warbler compels me to modify this statement somewhat. For us the aesthetic value of a song is quite an individual matter, subject to wide divergence of opinion. But for science it matters but little so long as some common ground for agreement can be found regarding that more important consideration, the question of relative development. We ought, that is to say,