PYROSOMA. 



523 



Pig. \m.— P)/ro.^oma {figanfenm.—T. A vertical section of Hie wall of the Apcidiarium 

 Tiear the cloaral aiieVrurc and includino- its lip. II. The younpest condition of a 

 bnd before the ecfoderm is elevated. III.. IV., V. Further stasres of the develop- 

 ment of a hnd. VI. A fully-formed bud with a second ascidiozooid in course of 

 development from its peduncle. 



