PLATE 22. 



Angelopsis dilata. 



Fig. 1. Radial section of the colony, a little to one side of the mid-plane, especially to show the 

 structure of the bulbous siphosome. From a photograph. X 9. 



Fig. 2. Radial section of the aurophore near the median plane. From a photograph. X 12. 



Fig. 3. A portion of the same more enlarged. X 30. 



Fig. 4. A similar section reconstructed from four adjacent .serial sections. Pn. C, pneumatocodon; 

 Pn. S, pneumatosaccus; En, endoderm; Ec', primary, Ec-, secondary ectoderm; Ch, chitinous la)-er; 

 Ca. P, pericystic space; Ca. H, hypocystic cavity. X 15. 



Fig. 5. Section through secondary ectoderm, chitinous layer, the evaginated portion of the pneu- 

 matosaccus, to show histology of the various layers. SI, stutzlamella; other lettering as in fig. 4. 

 X 250. 



Fig. 6. Longitudinal section through the wall of the nectosome in the lateral plane (transverse to 

 the aurophore). X 25. 



Fig. 7. Part of the basal portion of the siphosoine, to show positions of siphons (S), and their 

 connection with network of canals. Photographed from a dissection. X 20. 



Fig. 8. Small portion of the siphosome, showing branching canals. X 20. 



