\o6 



THE OCEAN WORLD. 



in length by two or three in breadth," says Sir J. G. Dalyel, " of a 

 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 



I'ig. 120. — Plumatella criotallina, 

 magnified (after Allman). 



Fig. 121. — Cristatella raucedo(Cuvier) 

 (after Allman). 



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 

 v/ith 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 lij^s, 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 



