The nervous system in the Cestode Moniezia ezpansa. 363 



hydrant water .... 100,0 ccm 



sodium chloride . . . 0,5 g 



pepsin . ..;.. > 1,5 g 



the results were still more satisfactory; but even with material col- 

 lected in this mixture neither GOLGI impregnations nor methylen-blue 

 stains were obtained. When killed in VOM RATH'S mixture material 

 collected in this fluid gave very good results ; but the best fluid found 

 for the transportation of the worms contained no sodium chloride. 

 It was composed of 



hydrant water .... 100 ccm 



pepsin 2 g 



egg albumen (fresh) 10 to 15 g 



Worms placed in this mixture appeared to suffer no harm even if left for 

 several hours provided the temperature did not go delow 10 C nor 

 above 30 C. With worms collected in this fluid a fair methylen- 

 blue intra-vitam stain was obtained, but, as my work was nearly at 

 an end before this solution was tried, I have not been able to test 

 it fully. 



For all ordinary purposes, preparatory to killing in the more 

 common reagents, I believe the worms could be collected in the 

 physiological salt solution without any appreciable change either in 

 cell arrangement or cell contents; but for the study of nerves the 

 material should not be placed in physiological salt solution, nor in 

 any solution containing sodium chloride. 



2. Keeping Cestodes Alive in the Laboratory. 



When the laboratory was reached the material was first washed 

 or rinsed in the fluid in which it was collected, or in a fresh supply 

 of the same, until it was free from all dirt and chyme. It was then 

 placed in a fresh, clean portion of the fluid, and finally in from 

 20 to 30 minutes after being taken from the animal, the worms were 

 ready for the killing reagents. 



In many cases it was found desirable to keep the worms alive 

 for a greater or less length of time, especially when the methylen- 

 blue process was employed. Attempts to keep the worms in any 

 mixture containing salt were fruitless, as they could not thus be made 

 to live more than a few hours at most. Distilled water and hydrant 

 water were both equally worthless, but after considerable experimenting 

 and many failures the following mixture was compounded, in which, 



