Bediae flontaining Daughter -Red! ae 



In thirteen snails of Physa o .ftcjL do n tali g taken from 



LaJ'-e, San Jranciaoo, redi-ie vith daughter *redicie inside, 



Although 

 were found* / j have rt*ver obtained very small rediae con- 



taining d vughter-rediae in these snails, :*nd altho I have 

 not traced th*> cycle of the daugyiter-redia^ yet, I feel 

 quite certain that there is only onu suoh generation* 

 Because of the fact that I believe only one generation of 

 daught'rr~r<diae to exist, I shall oall the rediae enclosing 

 daughter-rediae the raoth^r-rediae* These Eaother*rediae* 

 I fel quite certain, have been derived by metajaorphosiw 

 from miraoidia, * were the mother-rediae found in the 

 young experimental snails* 



i'he first ' a vid<moe i* that of the thirteen snails found 

 to harbor the iaother-rediae f eleven of the??e contained only 

 a few rediae, and of thene there were ne^er nacre than four 

 or five motlier-rediae, usually lees* In the two oases where 

 mother-rediie were feund in snails having many rediae pro- 

 duoing oercariae, these mother-rediae were limited to 

 Uiree or four in number* Had there been more than one 

 generation of daughter -rediae, then numerous rediae with 

 daughter-redime inside would lively be found since the 

 daughter* rediae *ad germ balls inside of one redir*e often 

 exceed seven ty//1h second evidence is that one generation 

 of daughter*r^dia coming by metamorphosis from a single 

 miracidium, is all that is necessary to produce the average 

 number of rediie found in a single snail* In case of two 

 or three hundred redime being found in one snail, that could 

 easily be explained by two, three or four miracidia finding 



