Sea and River-side Rambles in Victoria

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Samuel Hannaford. Sea and River-side Rambles in Victoria

Sea and River-side Rambles in Victoria

Table of Contents

CHAPTER I

CHAPTER III

CHAPTER IV

CHAPTER V

CHAPTER VI

CHAPTER VII

CHAPTER VIII

CHAPTER IX

CHAPTER X

RIVER SIDE RAMBLES

CHAPTER XI

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Samuel Hannaford

Published by Good Press, 2020

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CHAPTER XI.

But let us examine these suckers more closely, since they seem to act pretty much in the same manner as the leather toy we, as school-boys, amused ourselves ​with, and by them there can be little doubt that progression is effected. Their mechanism, we learn from Gosse,[3] is very simple. At the bottom of a furrow in each ray are rows of minute pores, through which the suckers are protruded, the base of each sucker being expanded into a little globular vesicle, which lies above the pore in the interior of the ray; the walls of this vesicle are muscular, and therefore contractile, and it is filled with a fluid. When an animal wishes to protrude and extend any given sucker, it contracts the vesicle at its base by an effort of the will; the fluid is thus forced into the tubular stem which is therefore compelled to elongate, and on the removal of this contractile force, the fluid returns to the bladder, either by the elasticity of the tube, or probably by its muscular action, and the sucker is gradually withdrawn.

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