(79) 

 corpuscle masses. Very large colls in close relation to the 

 bloc-j corpuscle masses are founci in some specimens of Actino- 

 trocha Species, B. ("^ig. 44(f) ) These cells reserr-ble the cells 

 \rhich I described in the old ^'astrula of Species, A., as arisinj^ 

 from the wall of the arete nteron, only they are not as coarsely 

 graiiulo.r as the latter. W.iile in Actino trcc.'ia Species, E. , the 

 cells are ■f'ound in most cases closely associated v/ith tiie blooa 

 corpuscles, I have never seen ti;em in the process of division 

 and 1 do not believe that they ^.jive rise to blood corpuscley. 

 Their occurrence is quite variable but as far as 1 have cbservea 

 ti''.ey are not presoiit in trie Ac t Inot rochae which are ready to 

 ••letamorphose. Tiiey are not phagocytes nor are they pigment 

 cells and the only name which I feel justifiea in givinf, them 

 is large free mesoderm cells. ^ 



Frequently they are also founa in the posterior end of the 

 trunk cavity. ("Pig.44(i) ) 



Roule (20) holds that the nephridia ena internally at the 

 level of the Oesophagus and he siio'vs this in a figure, 1 have 

 made cross sections throu;;'. this region ;ana have founa masses 

 of cells in much the same place as Houle has shown. These cells 

 ocem to me to be blooci corpuscles but I must say that I have 

 I ad opportunity to examine very few specimens and only one of 

 ineso showed th:ese masses of cells. 



