29. 



from my own wor)', it sterns prob.ibla that there Is definite 



grouping of flame oells and their capillaries connecting 



the accessory colli^tin<; tubuler?, ind th.it each group though 



modified thru increase, reduction or los* of parts ha?? come 



from the iflitctic division of ?. single flarae cell. In some 



oernariae AS 3 ohi 3 to soma japonicura or Ceronria dautihia.tti 



the capillary groups have not yt arinen sinoe the oapillarinn 



ire arrm^od singly, but X ahould 0xp*ot to find in the adult 



-worm eaohi capillary represented by a ;.;roup of flame cells. 



ln Mtinp.f- toina r.^ypj, u tu/i? the grcupu aro already precent ao in t 



alt I should expert to find the same number of flmae oells. 

 The excretory ^ - tern r?f th^ neroaria of ';!ohinpotf;ma ravo lutyto 

 has b^on modified accaewhat and i har*<l to interpret aa a 

 definite unified arrangement thruout. This theory of the 

 formation of capillary groups waa first given by Loosa 

 (1894) -md lator aonepted by Cert (191Ba) ^ven in 1881 

 (pi. 1, fi&. 4) Fraipont shews tha formation of tiro flatae cells 

 by mite tic division* 



In the oercriri?* of ^hinstomu v.jaryo.lut.uia. some times the 

 oc lleoting tubules and ?*gs*in the aonef?sory collecting tubules 



much reduced or have entirely disappeared as shown in 

 jre 47, 3c. This reduction or loss is liVely due to 

 severn 1 things, which might all be summed up by calling it 

 adaptation to the position they oooupy in the oercarias *body 

 or the position tny will eventually occupy in the body of 

 the adult echinostcae. 



The figure following represents graphically what i oonside 

 to be the generalized system of an eikinostome cercaria from 

 which the present system probably -ircee* The oomparison of thii 

 diagram with figure 47, illustrates a method by which the cap- 



