PLATE 21. 



Pig. 22. Crisulipora occidentalis sp. nov. An ocecial internode, shewing 



its origin in two zooccia in whose walls the first ehitinous joint (./.) occurs, 

 and the mode of formation of three branches; also, the oeecium (oe.) 

 distinguished by its coarsely punctate wall, with the tubular aperture 

 (oest. I.) and circular ooeciopore. The tubes at the distal extremity of the 

 internode, the proximal portions of which only are shown, give rise to 

 another internode. X 20. 



Fig. 23. Cr. occidentalis. Habit sketch. X 1. 



Fig. 24. Cr. occidentalis. A portion of the lower part of a colony 

 showing a rootlet (r.) which grows long, penetrating masses of other 

 material; another which is shorter and possesses a hook (h.) or process 

 which has laid hold of a grain of sand or a pebble; and a stolon-like 

 process (sto.) which grows horizontally sending up zocecia at intervals 

 which produce new branches. From the first zocecium (roe.) there arise 

 two tubes one of which gives rise to a double joint (d. j.) giving off 

 branches at an angle to each other and hence in different directions. 



Fig. 25. Tubidipora flabellaris Fabricius. A small colony showing its 

 origin in a primary disk (die.) and containing one complete ovicell (of.) 

 with typical ooeciostomal tube (oest. t.) and compressed ooeciopore (oep.) ; 

 showing also two immature ovicells (im. oe.). X 40. 



Fig. 26. T. flabellaris. An older colony than that shown in fig. 25, 

 showing an older stage of growth. X 16. 



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