PLATE XXVII. 



Fig. 1. — Surface of Stromatoporella eifeliensis, Nich., enlarged. Middle 

 Devonian, Gerolstein. 



Fig. 2. — Tangential section of the same, enlarged ten times, from the same 

 formation and locality. 



Fig. 3. — Vertical section of the preceding specimen, similarly enlarged. 



Fig. 4. — Specimen of Stromatoporella solitaria, Nich., of the natural size, 

 showing the characters of the surface. Middle Devonian, Gerolstein. 



Fig. 6. — Tangential section of the same, across one of the astrorhizal mamelons, 

 enlarged ten times, from the same formation and locality. 



Fig. 6. — Tangential section of the same, traversing a space between two 

 astrorhizal mamelons, similarly enlarged [erroneously referred in a paper in the 

 'Ann. and Mag. Nat. Hist.,' ser. 5, vol. xvii, pi. viii, fig. 5, to 8. eifeliensis]. 



Fig. 7. — Vertical section of the same, similarly enlarged. 



Fig. 8. — Tangential section of Stromatojwrella damnoniensis, Nich., enlarged 

 about ten times. Middle Devonian, Devonshire. (From the pebble beds in the 

 Trias of Teignmouth.) 



Fig. 9. — Vertical section of the same, similarly enlarged. 



