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PLATE XXXIV. 



PAGE. 

 Fig. 1. CONSTELLARIA PAKVA Ulr 424 



1. A fragment, of the natural size. . 



1 a. Tangential section x!8, showing the arrangement of the zoo?cia and 

 mesopores, around one of the stellate macula>. 



1 b. Vertical section xlS, showing the tabulation of the zoceeia and meso- 



pores. 



Cincinnati group, Wilmington, 111. 



Illinois Stale Museum. 



Fig. 2. TBEMATOPOEA? NITIDA Ulr 419 



2, 2 a and 2 6. Four fragments of this species. Natural eizo. 



2 c. The surface x!2, showing the form of the small zocecia apertures. 



Cincinnati group, Savannah, 111. 

 Illinois State Museum. 



Fij. r . '.}. TKEMATOPOBA DEBH.IS Ulr 419 



3 and 3 a. Two fragments of thig species, showing its mode of blanching. 



Natural size. 

 3 6. Surface xli 

 3 c. Tangential section x!8, showing character of zooecia interspaces, and 



small aeanthopores. 



3 d. Vertical section x!8. The mark at the bottom of the figure indicates 



the center of the branch. 



Top of Trenton, Alexander County, 111. 



Illinois State Museum. 



Fig. 4. LEIOCXEMA? WILMINGTONENSE Ulr 426 



4. Fragment, natural size. 



4 n. Tangential section x!8. 



4 l>. Vertical section x!8. The section passes a little obliquely though the 

 branch, causing the tubes to appear interiupted. 

 Cincinnati group, Wilmington, 111. 

 Illinois State Museum. 



Fig. 5. NlCHOLSONELLA PONDEEOSi Ulr 422 



5. An example of this species showing its regular mode of growth. Natu- 



ral size. 



