(1

Pelargonium zonale Roots

Nov. 21

Roots kept in sol. of C. of A. 4 to 1000 for 48° showed splendid granular matter — rounded, translucent irregular shapes, often more or less confluent—

Sometimes 2 or 3 row of cells adjoining with the granular matter — but usually alternate closely like E. peplus — close above tip opake lump, so the tip looks almost black. — Similar aggregated matter but larger granules in elongated cells & I think also in tube close to vascular bundle.— The most surprising fact is that root-hairs seem all to arise from the rows of cells free of aggregated matter; had it been otherwise this matter wd have passed into the hairs. —

Nov. 22d I examined 3 rootlets, which had not been in C. of A. & there was no aggregation— — One root was torn up & dissected — Irrigated with C. of A 7 to 1000 & after about 15' in one root which was

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Pelargonium

white, there was distinct granulation in the mostly alternate rows of cells. I neglected to look to endoderm vessels— In the 2 other rootlets which were brown & tips dead, there were in many cells small spheres of dark brown matter, but no distinct granulation. The epidermic cells in the torn fragments, but then these were brown roots were not well acted on.

Alcohol for about 20° after C. of A. for 48° (4 to 1000) & water for 6° does not destroy the granulation in the white roots or the brown spheres in the brown roots — There are many pitted vessels in the vascular bundles & round these much elongated cells & apparently tubes with hyaline, more or less aggregated grains. In one piece of tissue (with vascular bundle & opposite removed) so as to see clearly in this specimen, which had been kept in alcohol, I counted 30 hair-roots

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Pelargonium

arising from the colourless cells & not one from the granular cells, though I looked. In another piece of tissue I observed 20 hairs. I also observed others very near tip of roots, & all sprang from the colourless rows of cells. There was only 1 doubtful case where a root-hair seemed to arise from the junction between 2 cells, with granular matter but there seemed to be narrow white space between these 2 cells & this hair contained some granular matter. — (With respect to the degree of alternation of the colourless & granular cells; 2 granular rows often adjoin, & I I have seen as many as 6 adjoining.

On next page the arrangement in 2 cases is shown. It appears that certain rows of cells with root-hairs act as absorbents, & adjoining row serves for the elaboration & storage of matter, which is precipitated by C. of A. We can see that if hair-root opened into the cells with granular matter, this wd pass into the Hairs

[3v]

The granulation is in the epidermic cells

[slip of paper pasted on:]

[sketch:] arrangement of colourless tubes & those with granular matter.

(zz) (p 4) The C. of a. cause aggregation in the endoderm vessels & if appears that they must be alive & not much injured for this process to take place good (like Boiling water & alcohol with Eu. peplus).

24th 8° 45' irrigated this slide with caustic potash to see if the agg. matter will be dissolved, & reintegrated in the evening, & this morning (25th) the agg. matter though reduced was nearly all removed, & what is more remarkable the brown granular matter was still clear in the exterior cells. I can see that it is tubes or ducts in vascular bundle, with agg. matter.

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Pelargonium

Nov. 22d

A rootlet kept in C. of A (4 to 1000) for 48°, & then in water for 6° & then in cold caustic Potash for 20° — In one rootlet thin with perfect tip, no granular matter left in epidermic cells— In a second rootlet a trace left here & there, & some rows of cells were a shade browner than others.

In a thicker bit of root the agg. matter in the elongated cells or tubes round vascular bundle not dissolved, but rendered browner, & in other parts converted into oil-like transparent spheres; but perhaps potash had not penetrated this thicker root (a) (Back)

Novemb 23d 8° a.m. Roots which had been kept for 2 days in water, examined— no agg, exteriorly or in endoderm, & then irrigated with C. of A. 7 t 1000. — Nov. 24th. 8° 30' a.m There was aggregation or brown granules in the exterior cells; but in the vascular bundles, which had been freely exposed there was no aggregation. On tearing open part of same root, I found plenty of agg. matter in the endoderm vessels— This shows (zz)

[4v]

(a) At 12° on 22d fresh Caustic Potash was added to this specimen, & today Nov. 23d 8° 30' a.m I could see no agg. matter in endoderm tubes all dissolved, but there were oil-like globules in cells near vascular bundle. — So agg. matter both exteriorly & interiorly is dissolved by Caustic Potash.

N. B. Had it not been for the interior cells with agg. matter, I shd have thought that the brown granular matter in epidermic cells (though odd there shd be so many) was excretory, for brown matter after C. of Am. is thrown off in the loose cells of root-cap. — Possibly the brown matter alone is excretory — yet the agg. contents become in the cells & vessels near vascular bundle brown through caustic Potash

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Pelargonium

Roots left in sol. of 2 drops of 1 per cent— Osmic A. for 20 1/2 hr in 1/2 oz of distilled water, thus States of roots differed much, some very little blackened, but here & there a single epidermic cells with blackish granules & some small black spheres — Other roots much blackened, & on these there was plain alternation of blackened or browned longitudinal cells & colourless ones — Also blackened granular mater close to vascular bundle & in many parenchyma cells — I saw no exception to rule that hairs sprig from empty cells.