Pressure upon the Regeneration o/Gunda ulvse. 3 



cytology were stained with Heidenhain's iron hematoxylin followed by 

 orange Gr. 



II. Preliminary Experiments on Seduction and Growth in Whole 



Animals. 



(a) Reduction. 



A number of adult worms 5-6 mm. in length were washed in 

 sterile water and placed in a wide-mouthed sterile bottle which was closed 

 with a cork. Through this cork were passed two glass tubes forming the 

 inlet and outlet of an air-circulation, both tubes having a cotton-wool plug in 

 them to keep back chance organisms in the circulating air. The animals in 

 this apparatus were kept in a state of starvation. At intervals animals were 

 removed, measured, and fixed for sectioning. 



The worms were found to decrease fairly steadily in length under starvation. 

 Curve A in text-fig. 1 shows the course of diminution in length in an experi- 

 ment lasting 12 weeks. Microscopical examination of sections showed that 



6mm- — 1 1 1 1 1 1 1 1 



I » 



o io zo 30 40 50 60 70 80 90 



Days 



Fig. L 



Curve A, curve of diminution of length of starving animals. Curve B, curve of rate of 

 growth of starved worms on feeding. Note that feeding was interrupted between 

 22nd and 37th day. 



starvation is always accompanied by absorption of the generative system. 

 The yolk-glands appear to be absorbed first, but after the worms have been 

 reduced to about 4-5 mm. in length degenerative changes appear in the 

 ovary, testes and secondary sexual organs. By the time the worms are reduced 



B 2 



