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. inhcerens , such as one Avith 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. 
Plate and anchor of Synapta tenera, Norman, from Lochmaddy. 
o 2 
