﻿52 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 4/ 



Plate VIII 



Cyphotrypa acervulosa (Ulrich) p. 30 



Figs. 1,2. Vertical sections, X 20, of the immature and mature regions 

 respectively, showing variation in distribution of diaphragms 

 in these two regions (from type sections figured by Ulrich). 



3. Small portion of a tangential section, X 35, showing minute 



structure of walls and acanthopores in mature region. 

 Clitambonites bed of Galena-Trenton, Decorah, Iowa. 



Cyphotrypa wilmingtonensis new species p. 31 



4. Figure of a tangential section, X 20, illustrating the large acan- 



thopores and thin walls. 



5. Several zocecia of the same tangential section, X 35. 



6. Vertical section, X 20. 



Richmond formation, Wilmington, Illinois. 



Cyphotrypa frankfortensis new species p. 30 



7, 8. Tangential section, X 20 and X 35. 



9. Vertical section, X 20, showing distribution of diaphragms. 

 Top of Trenton formation, Frankfort, Kentucky. 



Atactopora angtilaris new species p. t> 2 



10. Tangential section, X 20, showing a macula, the ordinary zocecia, 



and the comparatively few acanthopores characterizing this 

 species. 



11. A portion of the same, X 35. 



12. Vertical section, X 20, the central portion of the figure showing 



edge of a macula. 



Lower beds of the Richmond formation, Waynesville, Ohio. 

 . Itactopora maculata Ulrich p. 31 



13. A zocecium, X 35; drawn from the type section figured by Ulrich. 



Fairmount beds, Lorraine formation, Covington, Kentucky. 

 Atactopora hirsuta Ulrich p. 31 



14. Tangential section, X 35, of a zocecium from the type section, 



introduced for comparison. 



L T tica formation, Covington, Kentucky. 



Plate IX 



Stigmatella crenulata new genus and species. (See also plate xiv, 1, 2). p. 34 

 Fig. j. Vertical section, X 20, exhibiting the crenulated walls of the imma- 

 ture region and the few thin diaphragms of the mature region. 



2. Portion of a vertical section of mature region, X 35, exhibiting the 



periodic development of the acanthopores. 



3. Tangential section, X 20, showing characters in a mature region. 



4. A portion of the same, X 40. The figure contains a macula and illus- 



trates the minute characters of the acanthopores and walls. 

 Lower beds of Richmond formation, Hanover, Ohio. 



Stigmatella spinosa new species p. 34 



5. A tangential section, X 20, showing, as usual in the mature regions, 



abundant acanthopores and the almost total restriction of meso- 

 pores to the maculae. 



6. Small portion of sime, X 40. 



7. Vertical section, X 20, of mature region. 



