SECT. V. 



.ROTIFEKA. 



167 



- 



derful instance of microscopic research, and of the per- ; 

 fection of the mechanism exhibited in the most minute 

 objects of creation. 



Fig. 137 represents the common Eotifer when its 

 wheels are expanded and when they are retracted. The 

 body is slender and flexible, 

 it is stretched out by longi- 

 tudinal muscles, and its girth 

 is diminished by circular 

 ones. The internal struc- 

 ture is similar to that of 

 the Brachion, but there is a 

 prominence or head between 

 the wheels on which there 

 are two crimson eye-specks, 

 and the foot terminates in 

 three concentric movable 

 tubes that can be protruded 

 and drawn in like the tubes 

 of a telescope ; each has a 

 pair of claspers to enable 

 the Eotifer to fix itself to 

 any object. 



The Eotifers are male and 

 female, but, like the greater 

 number of Infusoria, the 

 males are only produced at 

 intervals. The female Eoti- 

 fers have their perfect form 

 when they leave the egg : 

 they even come out of the 

 egg while it is attached to the tail of the mother, as 

 in the Brachionus pala (fig. 136). The males, when 

 hatched, have neither spines nor mouth, yet, during 

 their short lives, their motions are very fleet on account 

 of the vibrations of long cilia round their front. 



Fig. 1 37. Common Rotifer: a, mouth ; 

 b, eye-spots ; c, wheels ; d, probably 

 antenna ; e, jaws and teeth ; /, ali- 

 mentary canal ; g, glandular mass 

 enclosing it ; h, longitudinal muscles ; 

 i, tubes of water- vascular system ; 

 t, young animal ; /, cloaca. 



