Marvels of Pond-Life. 121 



were either spread like the corolla of a flower, or 

 permitted to hang dishevelled like the snake-locks of 

 Medusa. We will suppose these organs symmetrically 

 expanded, and that we are looking down upon them 

 with a magnifying power of sixty diameters, the light 

 having been carefully adjusted by turning the reflecting 

 mirror a little on one side, to avoid a direct glare. 

 The tentacles, each of which curves with a living grace, 

 and displays an opaline tint in its glassy structure, do 

 not form a complete circle, for at one place we discern 

 two slightly diverging arms of the disk, or frame 

 (Lophophore) from which they grow. 



These arms support tentacles on each side, and leave 

 a gap between, so that the whole pattern is crescentic, 

 or crescent-shaped, and not circular. Extending as far 

 as the points of the arms, and carried all round the 

 crescent, is an extremely delicate membrane, like the 

 finest gauze, which unites all the tentacles by their 

 basal portions, and makes an elegant retreating curve 

 between every two. Each tentacle exhibits two rows 

 of cilia, which scintillate as their vibrations cause them 

 to catch the light. The motion of the cilia is in- 

 variably down one side and up the other, the current 

 or pattern being carried on from one tentacle to the 

 other, all through the series. This characteristic, and 

 the facility with which each cilium can be distin- 

 guished, gives great interest and beauty to the spec- 

 tacle of this wonderful apparatus, by which water- 

 currents are made to bathe the tentacles, and assist 

 respiration, and also to carry food towards the mouth, 

 over which a sort of finger or tongue is stretched to 



