104. REPORT—1874. 
when irritated, just as the sensitive plant does; and he consequently regarded the 
capture of the aciewis insect as something merely accidental, and of no import- 
ance to the plant. He was, however, too sagacious to accept Ellis’s sensational 
account of the coup de grdce which the insects received from the three stiff hairs in 
the centre of each lobe of the leaf. Linnzeus’s authority overbore criticism, if any 
were offered; and his statements about the behaviour of the leaves were faithfully 
copied from book to book. : 
Broussonet (in 1784) attempted to explain the contraction of the leayes by 
supposing that the captured insect pricked them, and so let out the fluid which 
previously kept them turgid and expanded *. ‘ 
Dr. Darwin (1791) was contented to suppose that the Dionea surrounded itself 
with insect-traps to prevent depredations upon its flowers f. 
Sixty years after Linnzeus wrote, however, an able botanist, the Rey. Dr. Curtis 
(dead but a few years since), resided at Wilmington, in North Carolina, the head- 
quarters of this very local plant. In 1834 he published an account of it in the 
‘Boston Journal of Natural History’ {, which is a model of accurate scientific 
observation. This is what he said:—“ Each side of the leaf is a little concave on 
the inner side, where are placed three delicate hair-like organs, in such an order 
that an insect can hardly traverse it without interfering with one of them, when the 
two sides suddenly collapse and enclose the prey, with a force surpassing an insect’s 
efforts to escape. The fringe of hairs on the opposite sides of a leaf interlace, like 
the fingers of two hands clasped together. The sensitiveness resides only in these 
hair-like processes on the inside, as the leaf may be touched or pressed in any other 
part without sensible effects. The little prisoner is not crushed and suddenly 
destroyed, as is sometimes supposed, for I have often liberated captive flies and 
spiders, which sped away as fast as fear or joy could carrythem. At other times I 
have found them enveloped in a fluid of a mucilaginous consistence, which seems 
to act as a solvent, the insects being more or less consumed in it.” 
To Ellis belongs the credit of divining the purpose of the capture of insects by 
the Dionea, But Curtis, besides making out the details of the mechanism, by 
ascertaining the seat of the sensitiveness in the leaves, also pointed out that the 
secretion was not a lure exuded before the capture, but a true digestive fluid poured 
out, like our own gastric juice, after the ingestion of food §. 
For another generation the history of this wonderful plant stood still; but in 
1868 an American botanist, Mr. Canby, who is happily still engaged in botanical 
research, while staying in the Dionea-district, studied the habits of the plant 
pretty carefully, especially the points which Dr. Curtis had observed. His first 
idea was that ‘‘the leaf had the power of dissolving animal matter, which was then 
allowed to flow along the somewhat trough-like petiole to the root, thus furnishing 
the plant with highly nitrogenous food.” By feeding the leaves with small pieces 
of beef, he found, however, that this was not so, but that these were completely 
dissolved and absorbed; the leaf opening again with a dry surface, and ready for 
another meal, though with an appetite somewhat jaded. He found that cheese 
disagreed horribly with the leaves, turning them black, and finally killing them. 
Finally, he details the useless struggles of a Curculio to escape, as thoroughly 
establishing the fact that the fluid already mentioned is actually secreted, and is 
not the result of the decomposition of the substance which the leaf has seized. 
* Mém. de I’Acad. des Se. 1784, p. 614. t Botanic Garden, pt. ii. p. 15. 
+ Vol.i. pp. 128-125. } 
§ I am indebted to Mr. Warner, of Winchester, for pointing out to me that the seat of 
sensitiveness in the leayes of Dionea was discovered thirty years earlier than this by 
Sydenham Edwards, the botanical draughtsman. The fact is stated (1804) in the de- 
scription of plate 785 in the twentieth volume of the ‘ Botanical Magazine,’ then edited 
by Dr. Curtis’s English namesake. I quote Curtis’s remarks:—'These small spines are 
mentioned and figured by Ellis, and supposed by him to assist in destroying the entrapped 
animal; but that they are the only irritable points, and that any other part of the leaf 
may be touched with impunity, was discovered by our draughtsman, Mr. Edwards, several 
ears ago, when taking a sketch of the plant flowering at Mr. Liptrap’s, Mile End, and 
has since been repeatedly confirmed. ‘The same observation was made, without knowing 
it had been previously noticed, by our friend Mr, Charles Konig.” 
