306 THE OCEAN WORLD. 
in length by two or three in breadth,” says Sir J. G. Dalyel, “ofa 
flattened figure, fine translucent green colour, and fleshy consistence. 
Some of the shorter tend to an elliptical form, but those of larger 
dimensions are linear, with parallel sides and curved extremities. 
The middle of the upper and the whole of the under surface are 
smooth, the former somewhat convex, occasioned by a border of 
seventy or eighty, even up to 350 individual polypi, dispersed 
Fig. 120.—Plumatella cristallina, Fig. —Cri ‘ 
magnified (after Allman). oe a a a 
in a triple row, their number depending entirely on the size 
of the specimen. Each of these numerous polypi, though an 
integral portion of the common mass, is a distinct animal endowed 
with separate action and sensation. The body rising about a line 
above a tubular fleshy stem, is crowned by a head, which may be 
circumscribed by a structure of a horse-shoe shape, and bordered by 
a hundred tentacula. Towards one side, the mouth, of singular 
mechanism, seems to have projecting lips, and to open as a valve 
which folds up within, conveying the particles which are absorbed to 
the wide orifice of the intestinal organ, which descends, forming a 
