32 Transactions of the Society. 



two are outside the sucker-plate wliich is oblong and broader than 

 long ; there are two longitudinal rows of three circular suckers, one 

 row on each side of the median line, the two central suckers being 

 the largest ; on the outer side of each of these is a smaller circular 

 sucker, and each corner of the plate is occupied by an oval sucker. 

 Thus there are twelve suckers on the plate and two outside it. 

 The plate appears to have a strengthened margin and a rim round 

 each oval sucker. 



