PLATE VIL 



Tetradium lIuRONENSE, Billing,^, Sp. (Pago 25.) 



Figure ] . Fragment of the corallum of this species. Natural size. 



" ] a. Part of a large weathered specimen, showing successive laminm 

 with some of the conical elevations upon them. Natural size. 



'' 1 h. Part of a tangential section showing three or four short septa in 

 the cell-apertures. Enlarged about fifteen times. 



*' 1 c. Another part of the same section, similarly enlarged. 



'< 1 d. Longitudinal section, showing the tabulrc. Enlarged about fifteen 

 times. 



" 1 e. Longitudinal section showing on the upper edgo tlio surface 

 granules. Enlarged about fifteen times.* 



* Through an oversight this figure has been placed obliquely as rf^gards the 

 corallites ; it should be in the same position as figure 1 d. 



