PLATE XXVII. 



FIG. 



1-4. MEMBRANIPORELLA NITIDA, p. 200; various forms. 



5. , var. with small number of ribs. 



6. , primary cell. 



7. , group of cells in an early stage. 



8. , outline showing the structure of the 



cell. 



9. MEMBRANIPORELLA MELOLONTHA, p. 202. 

 10. - , nat. size. 



