Fact Number Four relates to its breathing. In 

 my serpent-star I traced what is known as "the 

 water-vascular system." This, in the common star- 

 fish, is nothing more than a hydraulic bellows ar- 

 rangement whereby each one of its tube-feet is 

 made to distend or to contract in the act of walk- 

 ing; it probably has no part in that animal's respir- 

 ation, this function being assumed by the multi- 

 tudinous dermal branchiae, or breathing-organs on 

 its back. This system is blind at the terminals, 

 which is to say, the tube-feet, but it opens at a 

 point on the upper side of the disk, where it is pro- 

 tected from the invasion of silt and similar foreign 

 matter, by the sieve-like madreporic plate. Now, as 

 my serpent-star was destitute of dermal branchiae, 

 and as it was further devoid of gill-like organs, 

 both externally and internally, it obviously was 

 only through the otherwise useless tube-feet that 

 respiration could be effected. More; I argued that 

 the entire water-vascular system was in addition a 

 sensory apparatus: the madreporite at one end 

 being the olfactory center, while the tube-feet at 

 the other were the tactile organs. 



Fact Number Five. This fact, the most indis- 

 putable of all, was that my animal was dead. But 



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