526 A. MILNES MARSHALL. 



series of specimens, showing all stages of this regeneration, and 

 I hope to be able shortly to describe the process in detail. 



That Antedou possesses this very extensive power of regene- 

 ration, greatly exceeding even that of Holothurians, was an 

 entirely new fact to me. Dr. Carpenter tells me that he was 

 led to suspect this long ago, and he has very kindly shown me 

 specimens that have been in his possession for many years, 

 which seem to me to be clearly cases in which regeneration 

 has been partially effected. Dr. P. H. Carpenter also tells me 

 he has known this fact for some time, though I believe no 

 notice of it has yet been published. It is only fair to add that 

 while at Naples the possibility that an eviscerated Antedon might 

 regenerate its visceral mass was suggested to me in conversa- 

 tion by Dr. Orley, of Buda-Pesth. I made very light of the 

 suggestion at the time, and was much astonished when a few 

 days later I found the specimen described above. 



The influence of the nervous system on the regeneration of 

 lost parts is a point concerning which we know very little ; but 

 the apparent ease with which this extensive regeneration is 

 effected in Antedon would certainly be still more surprising 

 were the main centre of the nervous system to be lodged in the 

 part lost, and so far may be regarded as an argument against 

 such a location. 



D. On the Functions of the Central Capsule. 



Experiment 4. — A specimen was eviscerated and allowed 

 to come to rest; a needle was then passed from the oral surface 

 down the canal surrounded by the First Radials (fig. 1) so as to 

 irritate the central capsule; the result was immediate flexion 

 of the arms, and in many cases active swimming movements of 

 the whole animal. 



Experiment 5. — A specimen was eviscerated and then cut 

 into two parts, one having two pairs of arms and the other 

 three. The central capsule, which was divided and freely ex- 

 posed by the operation, was then irritated by a needle. The 



