PLATE XI. 



Fig. ">o. Transverse oblique section through Actinotrocha Species A. Taken through region of origin of blood 



corpuscles. 14 tentacles. r V Oil Immersion. <4 0c. Camera. <293. 

 Fig. r.4. Transverse section through ventral cellar wall. Same specimen as that of fig. 53. Showing origin of blood 



corpuscles. T 'j Oil Immersion. 12 Zeiss ( 'oinp. Occnlare. Camera. 935. 



'.rocha Species B with ventral pouch evaginated. | Ob. X8 0c. Camera. X45. 

 Fig. 56. Actinotrocha Species A. Immediately before metamorphosis. | Ob. X40c. Camera. X56. 

 Fig. 56a. Actinotrocha Species A. Shortly after the beginning of metamorphosis. | Ob. X40c. Camera. X56. 

 Fig. 566. Metamorphosed A ctinotrocha Species A. | Ob. X4 0c. Camera. <56. 

 Fig. 57. Young specimen of Phoronis archiiecta ('.') with 30 tentacles. H Ob. X 4 Oc. Camera. X28. 

 Fig. 59. Metamorphosed Actinotrocha Species A. Transverse section through the region of the transverse septum. 



,', Ob. 8 Oc. Camera. X 240, 

 Fig. 60. Completely metamorphosed Actinotrocha Species A. Transverse section in region of branching of efferent 



vessel. J Ob. X8 0c. Camera, x 240. 

 Fig. 61. Adult Phoronis architects removed from tube. X8. 

 136 



