256 Preliminary Report on the Purbeck Characese. 



representative of this section being found in a fossil state. It is silicified 

 not preserved in limestone. 



EXPLANATION OF PLATE. 



Fig. 1. — Oogonium in utricle. 



Fig. 2.— Longitudinal sections of two fruits. 



Fig. 3. — Longitudinal section of part of branchlet, showing rosettes and a fruit attached. 

 Fig. 4. — Three fruits attached to branchlet, showing exterior of utricles. 

 Fig. 5. — Head, an elongated form, fractured obliquely. 



Fig. 6. — Transverse section of fruit, showing portions of adnate bract-processes. 



Fig. 7. — Utricle seen from above, with section of apex. 



Fig. 8. — Longitudinal section of fruit and part of branchlet (silicified). 



Fig. 9. — Transverse section of internode of stem, near thickened node, showing slight 



difference in size of sheathing tubes. 

 Fig. 10. — Two portions of stems showing rosettes. 



Figs. 11 and 12. — Transverse sections of spindles or heads, showing very unequal 



diameters of sheathing cells, and the bases of some branchlets. 

 Fig. 13. — Longitudinal section of spindle, showing base of ascending branch. 



