Plalc IV. 



Fig. 1. Meliceritiles durobrivetisis Greg Five zooecia witli opcrcula and tliree lietcrozooccia two of 

 wliicli aie provided with opercula. Chattiam. X 34. 



— 2. Tlie same species from Fecamp. Three heterozooecia. X 34. 



— 3. The same species. Two large lieterozooecia and tliree zooecia wliich liave been regenerated Ijv 



means of heterozooecia. Luton. > 34. 



— 4. llie same species. A regenerated zooecium witli operculum. Cliatham. > 34. 



— 5. The same species. Chatham. X 34. 



— Ü. The same species. A zooecium the aperture of whicli is almost perfectly closed by a concave 



lamina. There is only left a small opening in the distal half ChathRm. X 34. 



— 7. Meliceritiles diiiobrivensis, var. purviarmala. There is seen a number of small heterozooecia 



two of which in old zooecia, one zooecium with operculum and another with a concave 

 closurc-laniina. Gillingham. X 34. 



— 8. Meliceritiles durobrivcnsis Greg. There are seen four regenerated zooecia, the distal of which 



has been regenerated twice while the two at the left side have been regenerated several 

 times. Chatham. > 34. 



— 9. Mclicerililes uiidala d'Orb. X 34. 



— 10. The same species. Three zooecia have been regenerated bj' means of heterozooecia. X 34. 



— 11. The same species. Two regenerated zooecia with opercula. 



— 12. I he same species. Three heterozooecia one of which is intermediate between a heterozooccium 



and a zooecium. X 34. 



— 13. I'he same species. Two heterozooecia. X 34. 



— 14. The same species. A zooecium regenerated by means of a heterozooccium. X 34. 



— 15. The same species. A zooecium with a concave closure-lamina which is not yet du.scd in the 



middle. X 34. 



— 1{). The same species. A regenerated zooecium with operculum. > 34. 



— 17. The same species. X 34. 



— IS. Meliceritiles Lorieri d'Orb. Two zooecia with opercula. X 34. 



— HI. Meliceritiles durobrivcnsis, var. parviarmata. A portion of the incrusting base, consisting 



chiefly of heterozooecia. Chatham or Luton. X 2U. 



— 20. Two heterozooecia from the same colony. X (>ß- 



— 2L The same form. A jjortion of a two-layered colony with numerous heterozooecia. Basin de 



I'aris. X 34. 



— 22. Meliccrililcs penliiijouuin n. sp. Three heterozooecia. Tullstorp. X '^^- 



— 23. Mclicerililes Uull/iisi Pergcns. One of the two lieterozooecia shows a calcareous mandible. 



Gillingham. X 20. 



