CHAPTER II.

THE MOVEMENTS OF THE TENTACLES FROM THE CONTACT OF SOLID BODIES.

Inflection of the exterior tentacles owing to the glands of the disc
being excited by repeated touches, or by objects left in contact with
them--Difference in the action of bodies yielding and not yielding
soluble nitrogenous matter--Inflection of the exterior tentacles
directly caused by objects left in contact with their glands--Periods
of commencing inflection and of subsequent re-expansion--Extreme
minuteness of the particles causing inflection--Action under
water--Inflection of the exterior tentacles when their glands are
excited by repeated touches--Falling drops of water do not cause
inflection...19-37 [page vi.]


CHAPTER III.

AGGREGATION OF THE PROTOPLASM WITHIN THE CELLS OF THE TENTACLES.

Nature of the contents of the cells before aggregation--Various causes
which excite aggregation--The process commences within the glands and
travels down the tentacles-- Description of the aggregated masses and
of their spontaneous movements--Currents of protoplasm along the walls
of the cells--Action of carbonate of ammonia--The granules in the
protoplasm which flows along the walls coalesce with the central
masses--Minuteness of the quantity of carbonate of ammonia causing
aggregation--Action of other salts of ammonia--Of other substances,