A bladder was now experimented on, which was already somewhat affected by the surrounding water; for the spherical glands, though colourless, had their primordial utricles slightly shrunk; and the oblong glands were brownish, with their utricles much, but irregularly, shrunk.  The summit was treated with the solution of urea, but was little affected by it in 9 hrs.; nevertheless, after 23 hrs. the spherical glands were brown, with their utricles more shrunk; several of the other glands were still browner, with their utricles contracted into irregular little masses.

Two other summits, with their glands colourless and their utricles not shrunk, were treated with the same solution of urea.  After 5 hrs. many of the glands presented a shade of brown, with their utricles slightly shrunk.  After 20 hrs. 40 m. some few of them were quite brown, and contained [page 421] irregularly aggregated masses; others were still colourless, though their utricles were shrunk; but the greater number were not much affected.  This was a good instance of how unequally the glands on the same bladder are sometimes affected, as likewise often occurs with plants growing in foul water.  Two other summits were treated with a solution which had been kept during several days in a warm room, and their glands were not at all affected when examined after 21 hrs.

A weaker solution of one part of urea to 437 of water was next tried on six summits, all carefully examined before being irrigated.  The first was re-examined after 8 hrs. 30 m., and the glands, including the spherical ones, were brown; many of the oblong glands having their primordial utricles much shrunk and including granules.  The second summit, before being irrigated, had been somewhat affected by the surrounding water, for the spherical glands were not quite uniform in appearance; and a few of the oblong ones were brown, with their utricles shrunk.  Of the oblong glands, those which were before colourless, became brown in 3 hrs. 12 m. after irrigation, with their utricles slightly shrunk.  The spherical glands did not become brown, but their contents seemed changed in appearance, and after 23 hrs. still more changed and granular.  Most of the oblong glands were now dark brown, but their utricles were not greatly shrunk.  The four other specimens were examined after 3 hrs. 30 m., after 4 hrs., and 9 hrs.; a brief account of their condition will be sufficient.  The spherical glands were not brown, but some of them were finely granular.  Many of the oblong glands were brown, and these, as well as others which still remained colourless, had their utricles more or less shrunk, some of them including small aggregated masses of matter.]