THE ORGANIZATION 



Pectinatc.lla. Imagine a cylindrical tube to one end of which 



O %/ 



another tube, bent in the form of a horseshoe, (figs. 118, 119, //?,) 



i p \ ft 



Fig. 119. 



Fig. 118. 



is attached at a point which is equally distant from its two ends, 



Fig. 118. Pectinatella magnified. Leidy. 20 diam. A profile view of one 

 of the individuals of a compound, fresh-water Bryozoan. ek, efci, the gelatinous 

 envelope of the colony ; t to t 5 , the U-shaped double row of feelers ; lp, the 

 U-shaped arms ; m, the mouth ; I, the lip of m ; ee, the throat ; st, the stomach ; 

 s/l, the bottom of ,s< ; sfi, the anterior end of st ; cl, the valvular passage from st 

 to the last division (cl to an) of the intestine ; an, the posterior opening of the 

 intestine ; ac, the abdominal cavity, in which the arrows indicate the circulating 

 currents ; g, the nervous ganglion ; r to r 1 , the retractor muscles of the head ; 5, 

 the statoblasls, or so-called winter-eggs, in various stages of development from f 

 to s ; f, the posterior end of the ftmiculus, attached to the side of the body ; .si, 

 the anterior attachment of the reproductive organ. Original. 



Fig. 119. The same as fig. 118. A foreshortened view of the head, with the 

 body in the distance. The letters as in fig. 118, and in addition, c, the mem- 

 brane which passes from the base of one feeler to the other ; the arrows indicate 

 the direction of the currents of the circulating fluid in the U-shaped arms ; lp\ 

 end of lp. Original. 



