rOSITIOX OF THE MADREPORIC BODY. 65 



sorption of the larva (PI. VI. Fifjs. 2, 3, 4), in ^vhicli a line, drawn from 

 the madreporic body through the middle of the odd arm, would by no 

 means divide the Starfish symmetrically, confirms the above explanation 

 of the eccentricity in Echinometra. Supposing the spiral to have been 

 formed from the other side, the obliquity woul 1 be in the opposite direc- 

 tion. Of course this is simply a supposition on my part, which future 

 examination alone can verify; but it seems to me such a natural expla- 

 nation of the whole difficulty, that I give it here for what it is worth. 

 The multij^lication of madreporic bodies in many Starfishes need not in- 

 validate the view I have taken of its value, as we need only ascertain 

 which is the original one, the others being supplementary. I have found 

 larvce with two water-pores (madreporic bodies), but have never succeeded 

 in raising them. 



