318 NATURAL SCIENCE [May 



among the Metazoa. How then can this curious case of metagenesis 

 be interpreted ? Can the tube containing the embryos be considered 

 as the parent, of which the soma may be represented by the epithelial 

 tube, and by the internal cells which do not take part in the forma- 

 tion of the embryos ? One cannot help thinking of the cysticercans 

 and orthonectids ; but such comparisons may be rash at present. 

 We prefer to confine ourselves to the facts, waiting for their general 

 interpretation until the observations which we are pursuing on differ- 

 ent species furnish us with more copious data. 



Paul Makciial. 



