182 
Notes . 
of masses of usually short sclerotic cells, evidently derived from the 
parenchyma as stated by Moeller \ 
On treating sections of the old stem of the sunflower with phloro- 
glucin and hydrochloric acid, it was evident that in certain not very 
numerous cases the contents of companion-cells and sieve-tubes were 
stained in the same way as lignified walls. This was chiefly seen 
where lignification was just beginning in the walls of the elements to 
which the contents belonged. In the stem of the younger plant it 
was well seen in numbers of sieve-tubes and companion-cells in 
the parts of the phloem, which subsequently become lignified. 
In the main root of the older plant, at about 2 inches below the base 
of the stem (where the root was about f of an inch thick), none of the 
walls of the phloem-elements were lignified, but the contents of a large 
proportion of the companion- cells and sieve-tubes gave the phloro- 
glucin-reaction. The contents were much as one would expect to 
find in these elements (though apparently often showing signs 
of disintegration) : in the companion-cells fairly dense and often 
showing a nucleus clearly, in the sieve-tubes taking the form of a 
parietal layer often massed into a ‘ SchleimkopF on the sieve-plate, 
and giving the xanthoproteic reaction in both elements. The contents 
of these elements also gave reactions with aniline sulphate and with 
thymol, identical with those of the lignified walls of the same 
plant ; they further gave the coloration with chlorine and sodium- 
sulphite described by Cross and Bevan (p. 115) as characteristic of 
lignocellulose. The fact that the colour produced by the thymol- 
reaction is here, as in the lignified walls, blue-green would be 
taken, according to Molisch’s researches 2 , as probably indicating the 
presence of coniferin. Without going into such questions as the 
identity of lignin with coniferin, or with a mixture of coniferin and 
vanillin, or the occurrence of lignin in combination as a ligno- 
cellulose, as ^deduced by Cross and Bevan 3 , it may be pointed 
out that the facts described above, as far as they go, suggest that 
lignin may here be elaborated and accumulated in the cell-contents 
(in different manner or degree from what takes place in xylem- 
elements) before being infiltrated into, or combined with the cellulose 
composing the walls. From the material examined it cannot be said 
1 Moeller, Anatomie der Baumrinden, Berlin, 1882, p. 51. 
2 Molisch, loc. cit. 
3 Cross and Bevan, Cellulose, London, 1895, p. 94. 
