taeular eanals and in each segment sends out a pair 



of tentacles. 



Separating the radial water tujie from the nerve 



1:: to be round the radial perihaemal sinus. 



In Ophiurans a sub neural space- is present which 



is not represented in the Crinoid arm. This is due 



to the fact that in Antsdcn the nervous system is 



superficial while in Ophiurs it has been invaginated 



been 

 and with its invagination a space has also car^I .' 



A 



in below it. 



