Read it through once

These tendrils can be made to curve by a weight exceedingly small. The most sensitive part of our own skins is quite unable to distinguish so small a weight as is perceived by these tendrils. Even the sensation of taste can only be produced by a weight eight times as great as that shown by some of them. Tendrils curve very quickly after they have been touched. In twenty seconds some tendrils curve (_Cyclanthera_), others (_Passiflora_) take thirty seconds, and some of them require four to five minutes or even longer before they make up their minds to coil.