CONTROL OF HEAD FORMATION IN PLANARIA 



25 



to a considerable extent the increase of the rate of oxygen con- 

 sumption attendant upon section, and in some cases there were 

 indications that the rate of oxygen consumption of the pieces 

 in chloral hydrate had been depressed below the rate of whole 

 animals in water. 



TABLE 4A 



Head frequency — chloral hydrate. In per cent 



9/8, '20. 19- to 21-mm. worms. Fed two days before cutting 



11/20, '16. 15-mm, worms. Fed two days before cutting 



TABLE 4B 

 Oxygen consumption — chloral hydrate 



OXYGEN CONSUMPTION PER MILLIGRAM PER TWO HOURS 



First two houis Second two hours After 24 hours 



