1 84 



C. M. CHILD. 



different lots of worms more closely than if only the time of 

 complete disintegration were noted. 



In Table I. Lot I consists of ten worms 1.5-2 mm. in length, 

 which had emerged from cysts within three or four days preceding 

 and had been fed once with pieces of earthworm after emergence. 

 Lot 2 consists of ten worms 13-15 mm. which had been raised 

 in the laboratory from cysts with earthworm as food and were 

 almost ready to encyst again. 



TABLE I. 



Series 77. KCN o.ooi mol. 



It is evident at once from the table that the resistance of the 

 worms of Lot I recently emerged from cysts is very much less 

 than that of the large worms of Lot 2. Disintegration begins in 



