(C7) 

 thia aescriptioi^ tJ.at rlurin^ tha critical perioa, there i -s very 

 littiT ciir^ise -i ii 'i. .^■f-'-'-c rvr-e of the larval iiOi-hriaia or in 

 their rositiou, althoiu-jh the evatinat iovi of tt;._ vai"r.-.l pouch 

 ana the d'-a-.vin.,-. in of the ect^u-— /ri . i' ^i.c triinK to form the ena 

 of the rectum cauaea the amis to becoiric rather clos'^ly c<.pprox- 

 imatea to the external ne^J:;;-la1 .-.^ ^^..irxif^^, 



Cr-ld-/vell (3) says that the whole of the la'^v^j. n ,,.nriuiL-l 

 canals rerriainsas the pairea ncphridia o f the adult v/hile iKeaa 

 thinks it probable that only the parts of the nephrialu.1 canals 

 lying in the v. all of the trunk persist . He assumes that thie 

 neph^idial fimne Is of the adult, v/hich both open into th^' in- 

 fraseptal cavity, are secondary outgrowths of the above reirijiants 

 of the nephridial canals. 



As the nie tamo rpho sis contixiues, sections show ("Pig. 60) that 

 the excretor;,- cells ana that part of the nephriaial canals sit- 

 uated in the larval body cavity nave become obliterated tOL.ether 

 ith the portion o^ the ..e,n."jui,a ca..al.3 running in tnn septum. 

 While I do not vash to deny th^t the reirants of th^ nephxidial 

 canals and their exten^al openings, situatea originally in the 

 trunk cavity o- the Actinotrocha, become part of the nephridia 

 of the adult, yet in the stage unaer consia^..t icu, I am unable 



to ^ina that they exist. So far as I k 



no'v, Ike a a is the onlv 



investigator ....^.c ,;..» given us figures illustrating tl^ relation 



