sect, vni ROTIFERA, POLYZOA, AND BRACHIOPODA 179 



from the trochal disc, is frequently divided by a series of freely-movable 

 joints into a number of tubular segments like the parts of a telescope. 

 It is provided at its extremity in many forms with a pair of processes 

 which act like the blades of a pair of forceps in enabling the animal to 



Fig. 100. — BrachionUS rubens. A, from the dorsal aspect ; B, from the right side. 

 a, anus ; ir, brain ; d. f dorsal feeler ; c. gl, cement gland ; cl, cloaca ; c I, 

 ciliary lobes ; c. v, contractile vesicle ; e, eye-spot ; int, intestine ; lr, lorica ; 

 I. f, lateral feeler ; m, muscular bands ; npk, nephridial tubes ; ov, ovary ; fih, 

 pharynx ; si, stomach ; /, tail ; ir. d, trochal disc ; vt, vitellarium. (After 

 Hudson and Gosse.) 



temporarily attach itself. In many forms in which the tail is well- 

 developed locomotion may be effected not only by swimming by the 

 movements of the cilia of the trochal disc, but by creeping or looping 



