PERIVISCERAL FLUID OF ECHIXODERMS. 22() 



We know that the Echinoderms have great powers of regenera- 

 tion and may conclude, therefore, that all of the cells in the body 

 are very labile, but the question arises as to which cells in the 

 perivisceral fluid are the most generalized. Cells which could be 

 regarded as the most generalized would be those which are con- 

 stant in the perivisceral fluid of all of the Echinoderms and which 

 are observed to have diversified functions; those cells which 

 under nn < ssity of local needs remove foreign material, wornout 

 IIH nt- (if cellular origin and which could give rise to modified 

 Another : ! this investigation, then, is to determine 



if there .IP 1U in the perivisceral fluid, and if so, what 



i- the n. it lire of < ti\ ities. 



I. M \llkl\L AM) 



The material u-el in this investigation v. '.lerted in the 



vicinity of the I 5 1 ' ilogical Station, Friday Il.irb"r, 



Washington. K< [>n -i-ntatives of the four clas : luhino- 



derms found in this (-reused. The following are the 



which have i ..nniiied : 



< i ^SS I. .\~ii-i-oi.;. 



I . / 



nii. 



3. 2 icata. 



4. :tS. 



5. /.' ;.v. 



6. Henri: . iscnla. 



~. P : aides. 



( i tSS 1 1. Ophiuroiilea. 



I. C)/>///<'/'/;C.'/N- ''/. 



( "i ^SS III. 1 - hinoidea. 



i. > rotus drobachiensis. 



j. Strongylo( enlrotusfrandscanus. 



t v Echhnirnilnn'ns ccccntricns. 



CLASS 1\'. 1 lolothuroidea. 



1. CncHnniria japonica. 



2. Cucnnniria chronjhelmii. 



3. StichopHS californicus. 



