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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 8° 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 9° 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.

(4° 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)

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

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

(4° 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)

(7° 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 8° 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.