184 POPULAR HISTORY OF THE AQUARIUM. 



movement is effected. The retreating motion is performed 

 by a minute^ ribbon-like muscle, on which are fixed many 

 thousands of hooked teeth, which firmly hold to the inner 

 lining of the tube, while the muscles contract with a jerk 

 and draw the animal down. 



Amphitrite (?) jEgeana. — (Plate II.) 



On first visiting the Zoological Society^s collection, I no- 

 ticed spring up between the stones in a centre tank a trans- 

 parent, bell-shaped cup, formed by a circle of fan-like folds. 

 At the outer angle of each fold was a stiff-looking rib, end- 

 ing in a free, projecting point. The bell was about an inch 

 high, was placed upon a neck or stem, and had a funnel- 

 shaped hollow in the centre, towards which the inner angles 

 of the folds converged. It was not like the Anemones, for 

 there was no body to be seen ; and if the ribs, or projecting 

 points of the ribs, were tentacula, they were exceedingly 

 different from those organs in general. It was more like 

 Sahella, the feathery expansions of whose gills are such pleas- 

 ing objects, but there was a one-sidedness about these, that 

 was unlike the circular funnel of my stranger. Presently, 

 while wondering what it could be, it suddenly contracted, 

 folding itself up exactly as we do an umbrella, and looking 



