NORTH AMERICAN EARLY TERTIARY BRYOZOA. 



597 



The Cellepores are very difficult to study. Good specimens are rare, for the 

 erect zooecia are very fragile and are easily broken. The technique of their study 

 is quite difficult and still poorly established; the tangential sections are almost 

 impossible; the obliquity of the apertura renders the interpretation of the interior 

 difficult; the transverse sections give little information for their orientation is 

 difficult. The illustration by photography is quite deceiving and by drawing it 

 is very delicate. The preparation of the true illustration of a group of zooecia 

 of Cellepores has not yet been realized. 



A. Schismopora 



B. Osthimosia 



C. Costazzia 



D. Holoporella E Acanthionella F. Kleidionella 



FIG. 177. Genera of tlae family Celleporidae Busk, 1852. 



A. Scliismopora pumicosa Busk, 1894, X 30. Recent. 



B. Osthimosia evexa Jullien, 1S8S, X 35. Recent. 



C. Costazzia postazzii Savigny-Audouin, 1828, X 30. Recent. 



D. Holoporella descostilsii Savigny-Audouin, 1S28, X 25. Recent. 



E. Acanthionella oeeioporosa, new species, X 20. Claiboruian of Alabama. 



F. EleidioneUa grandis Canu and Sassier, 1917, X 20. Jacksonian of North Carolina. 



The recent specimens are more easily determinable ; their chitinous appendages 

 give excellent characters. Busk, MacGillivray, Waters, and Nordgaard have 

 arranged excellent comparative tables ; but they are still only of secondary impor- 

 tance to paleontologists. 



We are studying at this moment different processes of technique which cer- 

 tainly will give us excellent results in the future but the essential condition is 

 that our collectors should procure a large number of specimens in perfect preser- 

 vation. 



