MADREPORES. 185 
polyps simple or complex, with well-developed lamellar portions, the 
central culumn spongious, walls granular, semi-ribbed, and perforated ; 
the second have a reticulated sclerenchyma, septa more or less dis- 
woe the visceral chambers containing sometimes small rudimentary 
pilates. 
Fig. 68.—Dendrophyllia ramea, half natural size (De Blainville). 
We shall describe three genera, the two first of which belong to 
the Madreporine, and the last to the family of the Porztde. 
Dendrophyllia ramea, represented in Figs. 68, 69, and 70, is an elegant 
madrepore of the Mediterranean. Its polypidom presents a very 
large stem with short ascending branches ; it often attains to about 
