88 BY THE DEEP SEA. 



Looking at the underside of this Star, we find that each of 

 the rays is deeply channelled along its centre. Only the true 

 Stars have got this channel ; the Sand-stars and Brittle-stars 

 have not, neither have they got the wonderful suckers ; but 

 along each side of the channel, under each of Five-fingers' 

 arms, there are two rows of soft filaments that bend and wave 

 in any direction, and that end each in a little knob containing 

 a tiny limy plate. By means of this little plate each knob is 

 converted into a sucker, similar to those by which trades- 

 people suspend their goods from the surface of their plate-glass 

 shop-fronts, but worked by water instead of air. There are 

 hundreds of these to each ray, and all act in unison, so that 

 real progress is made when Five-fingers' olfactory sense in- 

 forms the sucker feet of the direction in which food may be 

 sought. 



Ah, you say, has it a nose ? No, it has not ; but experiments 

 have shown that the entire underside is sensitive to odours. 

 At the tip of each ray there is a spot that is ordinarily spoken 

 of as its eye, but it has no true eye, though these spots are 

 sensitive to light. Its mouth is in the centre of its under-surface, 

 and opens directly into the stomach, which has branches 

 running into each of the rays. The vent for the undigested 

 particles of food and for waste, is on the upper surface. 



Near the junction of two of the rays on the upper surface 

 will be seen a round stony knob, which is sometimes taken 

 for the creature's eye. This is not a very wild shot at its 

 purpose, though it is entirely a wrong one, for as placed it 

 certainly does suggest some such function. Its real office 

 could not suggest itself to any person unacquainted with the 

 internal economy of the Star-fish. Looked at through a lens, 

 it will be found to have a number of minute pores in its surface. 

 Strange as it may seem that the Star-fish should require such 

 a convenience, this is really a filter. Scientific men honour it 

 with the important-sounding name of the " madreporiform 

 plate," because its tubes resemble somewhat those of the 



