Nerve-Conduction in Cassiopea Xamachana. 5 



complex contraction waves proceed over it; but the larger waves travel 

 faster than the smaller ones and thus overtake, and combine with them, 

 in this manner forming a single component wave which appears upon 

 the kymograph record as a smooth and regular sinusoidal curve. 



All chemicals used in this research were Merck's " Reagent" in 

 quality. 



In taking these kymograph records a Jaquet chronoscope beating 

 seconds, or a make-and-break pendulum, was used with each individual 

 line, thus making the accuracy of the record independent of any 

 changes in rate of the kymograph drum. One ascertained the number 

 of seconds required for the contraction wave to travel 100 times around 

 the ring in pure sea-water; and then the number of times it traveled 

 around the ring in the same number of seconds in diluted sea-water 

 gave its percentage rate in the diluted sea-water. 



The average temperature of the surface water of the ocean at 

 Tortugas during the day time in June and July is about 29 C., and the 

 experiments of Harvey (1911), Mayer (1914), and Gary (1916), show that 

 the rate of nerve-conduction augments in practically a right-line ratio 



Sea waAer 30^4 



/vA/\/\J\ / sAxv/J[ / ^J\ / xy\^^ 



FIG. 6. Pulsus alternans, indicating the weak, exhausted, or pathological character of the 



conducting tissue. 



~R\T>a, stimulated inio 



FIG. 7. Three paralyzed rings being activated by induction shocks. A strong muscular 

 tonus is at once developed, irregular waves proceed from the stimulated region, and 

 finally a single regular sinusoidal wave going in one direction results from the inter- 

 ferences of the initial waves. The numbers represent successive attempts to stimulate 

 each ring, the last one being successful. 



