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July 27' tested secretion 2 nice young leaves & only just perceptibly & doubtfully acid with finest litmus paper— put on bits of meat with moistened with distilled water at 8˚ A.m — Tested another old leaf & not at all acid — Tested another with no acid —

A leaf contracting over meat, but not touching meat (which is acid) did just colour Litmus paper. — Also put gelatine on another leaf, which did not colour litmus paper.—

July 28th 9˚ tested the leaf with gelatine, but this not good because the gelatine had absorbed all from fluid— Tested the secretion from glands of the 2 leaves with meat, but of glands which did not touched meat, & manifestly & strong acid — The fluid bathing bathing meat intensely strongly acid (always judging by Litmus paper.) but this not quite trustworthy as meat is acid; but the secretion coloured the litmus paper far redder than the same meat moistened with distilled water.

(1

July 29th 1873 8º 30. (1) very large leaf on 1/2 dozen outer discals infl slightly sub-inflected towards glass — secretion slightly X acid— under the 2 fragments of glass on the disc, secretion extremely acid. The exterior glands not in the least inflected are not acid

(2) same as above but not quite so acid.— I tried the non-inflected X, exterior gland all round leaf & not acid.

Secretion of acid

(3) the sub- sub inflected outer discals & inner marginals decidedly acid.— X the fluid on the glass, under side very acid.— The glands of exterior non-inflected tentacles hardly acid, but one or two did show trace of acid

(4) With the inflected gland very little acid, just a trace; but under X the glass more decided — for no doubt of acidity, but less than last 3 specimens.

(5) The exterior glands not at all acid: the sub-inflected near glass slightly X acid — under glass decidedly acid— But the acidity nothing like the spec. with meat—

(Examined 6 leaves on same plate — & not which had never been inflected, 3 of these showed feeblest trace of acid— 3 not a trace — dabbed the litmus over gland of disc & exterior.)

Examined 5 young tender pale leaves on another plate, 3 with a trace of red or acid; 2 with no trace: examined 2 other older leaves which apparently had become firmly inflected & these showed decided acid or red.)

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July 28th 9º 30' tested with coarse bl litmus section of marginal & central glands of 5 leaves (marked with stick with paper & red band & pins) & they did not colour it— Put on bits of glass to see if acid when tents are contracted.

(4º 45' very decidedly acid, viz the somewhat inflected glands, near the piece of glass in all 5 leaves. Certain glands secrete much more than others for certain points on paper are much pinker than others. (we now have transmission of influence which increases secretion, leads to aggregation & alters character of secretion: we have here prefigured a recent & important discovery in Phy.— that nervous influence determines secretion: see Brunton)

(7º P.m. one of the leaves slightly acid) (see Back)

July 28' 12º 45' marked 3 leaves with Blue sticks & put on bits of meat, tested glands & secretion not acid with the coarse Litmus paper. —

(4º 40' the tentacles of on outside of disc, now stand vertically or a little inclined & have not touched meat, & are decidedly though only slightly acid)

(7º tried again no acid!) (tried an ordinary leaf with nothing on it & found it acid.) (I think the absence of acid may have been due to my having put on with meat a good deal of saliva)

July 29th 8º 29' — The gl secretion on glands, which have not touched the meat all 3 leaves, (closely inflected over meat) is now acid, & the fluid under the near extremely acid.