NO. 3.] STUDY OF STENOSTOMA LEUCOPS O. SCHM. 283 



coarsely granular nuclei (.V.) near their ciliated ends. The 

 nuclei are from 2 ^ to 2.5 <^ in diameter. No nucleoli were to 



^Thrcilia (C.) as seen in sections are very fine and nearly fiU 

 the lumen of the tube. In macerating a worm I have been able 

 o isolate from the body half the length of the ventral hmb of 

 the tube. In this condition the cilia were easily seen through 

 the transparent wall of the tube. i,„„„m 



The large amoeboid cells which form a cup from the bottom 

 of which' large cilium P™i-ts into the end^ of the very 

 fine branches (" Wimpertrichtern "), which Graff (82, p. 07) 

 describes for McsoJna EkrenbcrgU, and which Bohmig(90, 

 J 24") describes for Plas^os,on^a, could not be found either in 

 the living worm or in the sections. 



Graff ('82, p. .0.) says that the ^'er oscular systen^ 

 SunostoL kucops, which was first <'-"*^d^by Si bold ( 45 

 and Schmidt ('48) as a simple loop at the anterior end of the 

 body was followed further by Leuckart (-54). Leuckart de- 

 scribed it as an unpaired tube which opened at the posterior 



end of the body. . . 



Graff Cl'. P 415) from his own researches says that it is a 

 tube wh ch in the greatest probability opens at the posterior 

 end of the body. From this opening it runs to the anterior end 

 of th body, following the median dorsal line. Here it makes a 

 bend towa'i the ventral side, and proceeds backwards, ventra 

 to its former course. Since he was unable to trace it back of 

 the an erior one-third of the body, he surmised that the end of 

 the smaller tube was divided into fine branches in the anterior 



one-third of the body. , i ^ 4.1,^ 



° Landsberg ('87.,^ iv) agrees w.h Graff - -gari ^ th 

 relative positions of the limbs of the tube. He states that 

 he larger limb opens to the outside at the posterior end of the 

 bodj and also traces the branching of the smaller limb back as 

 far a«; the middle of the body. 



Zacharias ('85. p. 3.8), although he has not seen the conne. 

 tion thinks that on account of their location, contents and 

 analogy to similar cells in other forms, the pharyngeal cell of 

 mcr:Lna lineare .. not ^gestive but excretory mfuncto 

 and that they are in direct connection with the fine branches 

 the water vascular system. 



