12 



or one mother-rediae or norm. Also the shape at this time 

 is somewhat different from the daughter-radian* These four 

 fa^ts t-\y<*n together make me feel certain that there is nr 

 intervening; stage between the mi rani di a and the rediae 

 found in the experimental snails* 



The variation in ths <Use of these small mother- rediae 

 is due partially to th*5 degree of eon traction* They are 

 more sensitive than when mature since they <ion tract and 

 expand if slightly interfered with on a slide, Figure 19 

 shows 31 raother-redia in four different shapes due to the 



r^ of oontraoticn, Jlnure 19a shows the raother-redia 

 to be almost 8*o*3h*p9d with no tra<*e of tli posterior 

 orotrueions. Pigure19b t q and d show? the posterior pro- 

 trusions becoming ;aore prominent as the length increases* 

 The blind intestine alec shortens and lengthens with the 

 body* The variation of the sise of the blind intestine 

 is eharaoteristiG at this tr*ge of development. 



Because of the opaqueness of the body of the young 

 mother-redia, the germ balls oould not be made out although 



they are undoubtedly a large and as numerous R they 



. 



were in the 



How lone it trtfrefc the mother- redin to develop to 

 Maturity and to produoe another partheno genetic generation 

 is as y?t undetermined but quite lively it is accomplished 

 in about three months during the warmer weather* 



Thff g"jrra b.ills on the inside of the mother-rediae undout 

 edly develop into daughter -rediae, but 1 oannot be certain 

 whether there is more than one generation of daughter-rediae 

 sinoe this stage has not been followed throughout the entire 



