-it -.ill to trtutnniK ulfuwii il naiworia , 7, 



PLATE LXIX. 



PAGE-. 



Fig. 1. CYCLOPOBELLA SPINIFEBA Ulr ...................................................... 675 



1. Under surface of a specimen, natural size. 



Keokuk group, Warsaw, Illinois. 

 Illinois State Museum. 



1 a and 1 6. Two portions of a tangential section, x28, one with a macula. 

 The hemisepta which may be seen in nearly all the zooecia cavities are 

 not represented. The acanthopores are also not distinct enough. 

 They are nearly as conspicuous at this magnification as in flg. 3 a. 



1 c. Portions of two vertical sections, x!8, showing the strong acanthopores 



and superior homisepta. , 



Fig, a. STICTOPOBEXLA? BASALIS Ulr. (See also PI. LXVII1, and LXXV) ............. 532 



2. The erect portion of a zoarium split through the center so as to expose 



the surface of the median lamina; natural size. 

 Keokuk limestone, Warsaw, 111. 

 Illinois State Museum. 



2 a. Vertical section of same, x!8. The lower portion of the tubular zooacia 



is incorrectly drawn. (See plate LXXV.) 



Fig. 3. CYCLOPOBEIJjA? PEBVEBSA Ulr ..................................................... 676 



3. Tangential section, x!8, showing the usual appearance. 



3 a. Portion of same, x50. The acanthopores are more numerous and 



stronger than usual. 



3 6. Vertical section of a parasitic example, x!8. The transversely lined 



body entering the section from the right represents one of the project- 

 ing surface lamellae of the lamellibranch shell upon which it grew. 



Fig. 4. PBOUTELLA DISCOID EA Prout ....................................................... 674 



4. The under side of a specimen, natural size. 



Keokuk group, Warsaw, 111. 

 Illinois State Museum. 



4 a. Upper side of a fragment, natural size. The cell apertures should 



have been drawn in diagonally intersecting rows. 



Nauvoo, 111. 



E. 0. Ulrich's collection. 



4 6. Surface of 4 a, x9, showing usual arrangement of cells. 

 4 c. Portion of same, x!8. The thin cell front and the true orifice, are not 



shown, having first been discovered, after the plates were printed. 

 4 d. Thin section, x28. The anteriorly perfoi ated diaphragms, which are 



dimly shown in this section, are not represented in the drawing. 



