ECHINODERMATA. 



99 



whole plate is much larger, and there are generally seven 

 apertures round the central, instead of six as in the former 

 case ; while the slits in the smaller end (to which the anchor 

 is attached) are much more numerous and linear. Various 

 abnormal anchors occur in S. inkcerens, such as one with five 

 flukes (a bifid process on the summit, a bifid fluke and a 

 normal serrated fluke), or an anchor with several processes on 

 the stalk. 



^ 



li 



Plate and anchor of Synapta teiwra, Norman, from Lochmaddy. 



02 



