WHEEL-BEAKEBS. 227 



ance is produced entirely by the alternate bending and 

 rising of the ears of corn, which are of course stationary. 



The beauty and wonderfulness of these ciliary wheels 

 are so striking, especially when one sees them for the first 

 time, that for awhile we see nothing else ; we cannot take 

 our eye off from them. But when you have a little satis- 

 fied your sense of seeing, you may examine other points 

 of interest in this charming little animal. 



The cilia are remarkably stout and long in this genus, 

 but on the middle lobe of the front there are other pro- 

 cesses of the same character ; but still stouter. These 

 too are not properly vibratile, at least they do not make 

 circular wheels : ordinarily, they project like stiff erect 

 bristles, or converge towards each other. 



Between the two middle spines the shell is cut into a 

 d^ep notch, out of which protrudes, when the wheels are 

 expanded, a curious little organ, consisting of fleshy tubes, 

 the one sheathed in telescopic fashion within the other, 

 and bearing at its tip a pencil of bristles, which can in 

 turn be sheathed. This organ doubtless represents the 

 united antennas of insects. 



But, you ask, what is that much more conspicuous 

 organ that is alternately thrust out and drawn back at the 

 bottom of the shell, and that is so nimbly whisked about 

 in all directions, looking, with its numberless transverse 

 wrinkles, and its little fingers at the tip, so like an ele- 

 phant's trunk in miniature ? This is the creature's foot ; 

 the only one he has ; and as I said the little tubular tele- 

 scope represents the two antennae fused into one, so we 

 must consider that this flexible member represents all the 

 six pairs of an insect's legs united, or perhaps, more scien- 

 tifically, one of the pairs, the rest being obsolete or un- 

 developed. It must not be considered as a tail, not only 

 from its function, which is decidedly that of locomotion, 

 but also from its position on the ventral side of the intes- 

 tinal orifice. It is a curious organ, capable of great elong- 

 Q2 



