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. 
Fig. 177. — Genera of the family Celleporidae Busk, 1S52. 
A. Schismopora pumicosa Busk, 1894, X 30. Recent. 
B. Osthimosia evexa Jullien, 1888, X 35. Recent. 
C. Costazzia costazzii Savigny-Audouin, 1828, X 30. Recent. 
D. Eoloporella descostilsii Savigny-Audouin, 1828, X 25. Recent. 
E. Acanthionella oecioporosa, new species, X 20. Claibornian of Alabama. 
F. Kleidionella grcmdis Canu and Bassler, 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. 
