A strange and, so far as I am aware, an unparalleled phenomenon is sometimes manifested by Sarsia after removal of ganglia. It only happens in about one case out of ten, and _never_ except in response to either chemical or electrical stimulation. A bell quite paralysed, and which may have responded normally enough to stimulation for a number of times, suddenly begins an active shivering motion, which may last from a minute to half an hour. This motion is totally different from anything exhibited by the animal when alive, and after ceasing never recommences without fresh stimulation. The shivering appearance, I think, is due to the various systems of muscles contracting without co-ordination, but why it should take place in some cases and not in others, I am quite unable to determine. Irritability of bell to shocks increases progressively from centre to circumference, and is greatest when electrodes are placed on marginal canal. Also a similar progressive increase is observable on approaching one of the _radial_ canals, and is greatest when electrodes are placed on one of these. (I may observe that however neat a person's fingers may be it would be simply impossible to conduct these and other observations of the same nature without a mechanical stage. The electrodes must be needle-points passed through cords, the latter being supported by a copper wire fixed to the stage, and therefore moveable with it; and I defy anybody to get the electrodes into the field, and at the same time upon the marginal canal, unless they all move together.) [Illustration: FIG. 2.] Sarsia stands an astonishing amount of section without losing nervous conductibility. For instance, the whole organism may be cut into a three-turned spiral, and on irritating the end, the whole contracts; yet a moment's thought will show how trying this mode of section is to nervous connections. As the animal may be cut, as in the following diagram, which represents the whole organism in projection--the dotted lines being the canals, and the thick ones the cuts--on now irritating any part of the animal, the whole contracts, but the co-ordination power is lost, both in spontaneous contraction and for those in response to stimuli. If the entire margin be cut out in a continuous piece save a small portion to unite it with the bell, and if the distal end be now irritated, a main of contraction runs along the entire severed part till it arrives at the small united part, when the whole bell contracts. I should like to try whether under such circumstances the margin would be thrown into a state of electrotonus, but only having one cell I am not able to make out this point satisfactorily.