EEPOETS TEOM THE SECTIONS. 301 



tliat of eiglit caused an exceedingly feeble and sometimes doubt- 

 ful tinge of red. Two otlier old leaves, boweyer, wliich appeared 

 to bave been inflected several times, acted mucb more' decidedly 

 on tbe paper. Particles of clean glass were then placed on five 

 of tbe lea^ves, cubes of albumen on six, and bits of raw meat on 

 tbree, on none of wbicli was tbe secretion at tbis time in tbe least 

 acid. After an interval of twenty-four bours, wben almost all 

 tbe tentacles on tbese fourteen leaves bad become more or less 

 inflected, I again tested tbe secretion, selecting glands wbicb bad 

 not as yet reacbed tbe centre or toucbed any object, and it was 

 now plainly acid. Tbe degree of acidity of tbe secretion varied 

 somewbat on tbe glands of tbe same leaf." 



Tbe secretion so discharged has been examined by Dr. Darwin, 

 in order to ascertain whether this acrid matter approaches to tbe 

 gastric juice or digestive material found in the stomachs of 

 animals, and the experiment showed that " the acid belongs 

 to the acetic or fatty series" (see page of "Insectivorous 

 Plants" 88.) 



Professor Frankland observed of the fluid taken from tbe 

 filaments of Drosera rotundifolia that "when acidified with 

 sulphuric acid it emitted a powerful odour like that of pepsin." 



By tbe kindness of Mr. Hirst, tbe Secretary of tbis Section 

 of tbe Koyal Society, I bave been enabled to examine with bis 

 microscope the structure of these plants, more especially Drosera 

 hinata. On placing one of the tentacles of tbe latter under a 

 low magnifying power its structure is fairly displayed. It con- 

 sists of a straight, pale green hair, carrying at tbe end a balloon 

 or pear-shaped gland, of a red or scarlet hue, in some cases more 

 brilliant than others ; but on increasing the power to 1,400 

 diameters, by a sixteenth inch immersion lens, the character of 

 the gland is more clearly defined. "We see that tbe spiral vesicle 

 which traverses the centre of tbe pedicel increases in breadth as 

 it approaches the gland, and divides into two branches, each 

 branch of which, as it reaches tbe centre of the gland, 

 doubling backwards and forwards on itself several times, the 

 whole at first sight having the appearance of pistil of a poppy. 

 The spiral vesicle passes from the gland down the pedicel to the 

 mid-rib of tbe frond, and in that also, upon further investigation, 

 can tbis spiral arrangement of cells be found. 



Tbe pedicel bearing the gland is apparently divided lengthwise 

 into rows of elongated cells ; those contiguous to the spiral for- 

 mation being filled with a fluid containing granules of matter, 

 frequently found in an aggregated condition, but having an 

 ever-changeful irregular motion. This matter is frequently 

 understood by tbe word ^''protoplasms In Drosera rotimdifolia^ 

 Darwin states that in tbe course of a few minutes be has noticed 

 these germs undergo many changes, and that they pass up and 



