368 E. R. CUMJXGS POSITION OF THE MONTICILIPOKOIDS 



Figure 9. — Vicu: of the iniiiul Rv<iion of an unusuully iccll preserved tSpeeimen 

 of Pru-s'oiJora conoideu, us seen hij reftcetrd Light. 



Note that the point (initial portion) of the bud e is not in contact with 

 the ancestruhi and therefore could not have originated from it. x ^•^• 

 Cannon Falls,' Minnesota, Phylloporina bed. (106-16.) 

 Figure 10. — A yoiiiif/ CoJoin/ of the recent Bnjozoan Schizopontia, after 

 Harroh. 



Showing the similarity of arrangement of the zooecia to thai seen in 

 figure 9. X 10. 

 Figures 11 and 12. — Side and hasaJ Views of a tjouHfi Colony of the coral 

 Pleiirodictyuni lenticulare. after Beeclier. 



Showing the totally different form and arrangement of the initial indi- 

 vidual of the colony and the primary buds from that shown iu figure 9. 

 The buds appear in the order of the numerals. Note that seven buds arise 

 from the initial individual and are symmetrically arranged about it. 



xi%. 



Figure 13. — .1 diayrannnatic Drairiity from a Photoyrayli of a Section throuyh 

 the initial Region of Peronopora pavonia (D'Orh.). 



Showing the ancestrula and primary buds and the arrangement of the 

 zooecia in the basal expansion of the colony. The origin of the median 

 lamina is shown at I and /'. X 9- Cut No. VIII. Tanner's cr. Upper 

 Lorraine. (104-1.) 



Plate 20. — Development of the Monticuliporoids 



Figure 14. — Initial Region of Peronopora pavonia {same Specimen ax Figure 

 IS). 



This section is too high in the colony to cut the protoecium. but shows 

 the ancestrula and primary buds. The conspicuous thickened wall bound- 

 ing the ancestrula and primary buds is sho^^^l at x-x'. x ^•^»- (104-1.) 



Figure 15. — Semi-diagrammatic Brairiug from Figure 1). 



Figure 16. — Transvevse Section through Ihc initial Rcf/ioii o/" Callopora ramosa 

 (D'Orh.). 



At a level similar to that of figure 14. X "l-^*- <^^it No. VIII, Tanner's 

 cr. Upper Lorraine. (106-17.) 



Figure 17. — Transverse Section througli the initial Region of a Callopora (.') 

 from the Phylloporina Bed, Canno)i Falls. Minnesota. 



In this specimen there was a void iinmetliately i^osterior to the protoe- 

 cium as in the recent Discoporella (cf. figure 41). This clearly shows that 

 no posteriorly directed buds arose from the ancestrula. X 43. 



Figure IS. — Semi-diagra)nmatic Drauing from Figure 29. X 't^- 



Figure 19. — Diagratnmatic Drawing of the initial Region of Phylloporina cor- 

 ticosa Ulr. 



Showing the origin of the Fenestella-like rays. The section cuts at a 

 higher level than figure 18. x '^'^- Phylloporina bed. Cannon Falls. Min- 

 nesota. (56-6.) 



Figure 20. — Vertical Section through the Ancestrula. etcetera, of Prasopora 

 conoidea, with Lines m-m', etcetera. 



To show the level of various transverse sections. (Same specimen as. 

 figures 21, 22, and 35.) X 30. 



