Yabulate Corals with existing Species. 193 
ever, these septa are to be found, but they are usually more re- 
and less evident than in A. spongiosa, while the walls in 
most of.the other species are thicker and perforated by fewer 
and smaller openings, thus producing firmer corals. In A. 
dedalea Dana* the walls are much thicker and perforated by 
smaller, rounded orifices, of which there are two or three verti- 
cal series on each side of acell. The cells are very deep and 
the transverse septa are complete though distant, and coincident 
in adjacent cells. The radiating septa are represented by twelve 
vertical rows of stouter spines, which often meet at the center. 
numerous and thin, usually irregular, but with an evident ten- 
deney to coincide in height in all the chambers of the same 
* This Species, which proves to be distinct from the dedalea of Forskal, etc., has 
Tae ame 4 Versdieea by Prof. Dana in his recent work on Corals and Coral 
t Annals and Magazine of Natural History, vol. vi, p. 384, Nov., 1870. 
Am. Jour, Scl.—Turep Series, VoL. III, No. 15.~—Maxcu, 1 
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