THE KOMANCE OF NATURAL HISTORY, 



sedimentary matters that have become entangled 

 in its outer surface. It seems to be deposited pro- 

 gressively, — a mucus excreted and thrown off by 

 the skin of the tenant ; and hence the upper por- 

 tion, being the most recently formed, is destitute 

 of such extraneous substances, and can with the 

 greatest difficulty be traced to its termination. 

 Within this tube resides the beautiful constructor ; 

 a very slender foot or pedicle, capable of being 

 drawn out to such a length as to equal that of 

 the tube, and of being suddenly contracted at the 

 pleasure of the animal, merges into an ovate body 

 of translucent flesh, in which all the organs are 

 clearly visible. The upper portion expands into a 

 most exquisite disk or shallow cup of clear gela- 

 tinous membrane, having five angles, each angle 

 being terminated by a rounded knob. Each of 

 these five knobs is the seat of a pencil of long 

 straight bristles, of the most subtle tenuity, which 

 look as if they had been drawn out of the finest 

 spun-glass. There may be perhaps fifty hairs in 

 each pencil, which radiate from their common base 

 in all directions, and, as they are graduated in 

 length, the effect of these hairs is most charming. 

 Any little shock, such as a jar to the table, or the 

 shutting of a door, alarms the beautiful creature, 

 and it suddenly closes up its elegant flower, and 

 retreats into its tube, the hairs forming a cylin- 

 drical bundle as it goes down. It presently 

 emerges again, however, and unfolds its array as 

 before. The pencils of hairs are carried quite 

 motionless when expanded, but when the united 

 bundle is in the act of protrusion, a kind of thrill, 

 a quivering wave, is frequently seen to run 

 through it from end to end. There is a wreath of 

 rotating cilia on the face of the disk, the effect of 

 which is to draw floating bodies around into its 

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