1876 



MEDUSAE 



29 



the dotted lines being the canals, and the thick ones 

 the cuts on now irritating any part of the animal, 

 the whole contracts, but the co-ordination power is 

 lost, both in spontaneous contraction and for those in 

 response to stimuli. 



If the entire margin be cut out in a continuous 

 piece save a small portion to unite it with the bell, 

 and if the distal end be now irritated, a main of 

 contraction runs along the entire severed part till it 

 arrives at the small united part, when the whole bell 

 contracts. I should like 

 to try whether under 

 such circumstances the 

 margin would be thrown 

 into a state of electro- 

 tonus, but only having 

 one cell I am not able to 

 make out this point satis- 

 factorily. 



The severed margin 

 continues its rhythmical 

 contractions for two or 

 three days. I am now trying the effect of different 

 chemical stimuli, and if you can suggest any further 

 line of experimentation, of course I shall be very 

 pleased. Only, if you can think of anything which 

 might be tried and which is not mentioned in this 

 letter, please write soon, as the Sarsia will not last 

 much longer, and they are the best adapted for my 

 purposes. 



I remain, very sincerely yours, 



GEO. J. ROMANES. 



FIG. 2. 



