396 LILY HUIE. 
ribbons by Mann’s! egg-albumen method, and stained either 
by M. Heidenhain’s iron-alum hematoxylin (with or without 
previously staining in Bordeaux red), which gives very good 
results for the merely morphological aspects; or by Mann’s? 
eosin and toluidin blue method, for the study of the alkaline 
and acid reactions. In every stage of stimulation the staining 
reaction was controlled by having on the same slide a row of 
sections of unfed material. The method of staining with 
eosin and toluidin blue is as follows :—Free the sections from 
paraffin by xylol; remove the xylol by alcohol; place the 
sections in Gram’s iodine solution (double strength) for 
five minutes; wash out the greater part of iodine with 
alcohol. 
Wash in water till the sections are quite white; place in 1 
per cent. watery solution of water-soluble eosin (Gribler) for 
fifteen minutes ; rinse in water; place in 1 per cent. solution 
of toluidin blue for five minutes; rinse in water ; decolourise 
in absolute alcohol till the control sections upon the slide 
appear as on fig. 1, or pale blue to the naked eye. It is very 
essential that the absolute alcohol is pure, or otherwise the 
blue colour will be extracted too rapidly by the lime which is 
used in the distillations of alcohol. Further, do not allow the 
alcohol to drop on the slide, because this causes unequal 
washing out; but always immerse the whole slide in a vessel 
filled with absolute alcohol; clear in xylol by immersing the 
slide, and mount in turpentine or xylol balsam. 
GENERAL STRUCTURE OF THE GLANDS. 
In the heads of the tentacles of Drosera rotundifolia, 
D. dichotoma, &c., we may distinguish between glandular 
and non-glandular elements (see the accompanying figure). 
The latter consist of a group of large tracheids forming the 
1 Mann, G., “ A New Fixing Fluid for Animal Tissues,” ‘ Anat. Anzeiger,’ 
vii Jahrg. (1893), Nos. 12 u. 13, p. 442. 
? Mann, G., ‘ Zeitschrift f. wiss. Mikrose.,’ xi, 1895, p. 489. 
