CO-ORDINATION, 145 
ever, peripheral irritability returned, as shown by 
responses to nipping of the neuro-muscular sheet. 
The animals were now in the same condition as 
when anzsthesiated by caffein or other central 
nerve-poison; but in a few minutes later central 
or reflex irritability also returned, as shown by 
single responses to single nippings of the tentacles. 
Last of all spontaneity began to return, and was 
in some few cases conspicuously marked by a want 
of co-ordination, all parts of the margin originating 
impulses at different times, with the result of pro- 
ducing a continuous flurried or shivering movement 
of the nectocalyx. After a time, however, these 
movements became co-ordinated ; but in most cases 
when a swimming bout had ended and a pause 
intervened, the next swimming bout was also in- 
augurated by a period of shivering before co-ordina- 
tion became established. This effect might last for 
a long time, but eventually it, too, disappeared, 
the swimming bouts then beginning with co-or- 
dinated action in the usual way. , 
