532 Vei'rill, Notes on JRadiata. 



calicles are nearly circular unless crowded, — though often appressed 

 wliile young, — and deep at the center. Columella often rudimentary, 

 when most developed composed of rough, irregular, twisted and con- 

 torted processes, arising from the inner portion of the septa and 

 uniting at the center, with a ragged upper surface. Septa very un- 

 equal, forming three or four cycles, tlie fifth sometimes imperfectly 

 developed in some of the systems ; the primaries and secondaries 

 much the broadest and most exsert, with the summits broad and en- 

 tire, or but slightly denticulated ; within, toward the base, thin and 

 usually narrowed and then expanded again into a slightly marked 

 paliform lobe, the sides strongly granulated ; tertiaries narrow at 

 summit and slightly exsert, the edge strongly denticulated ; those of 

 the fourth and fifth cycles narrow and thin, with denticulated edges, 

 those of the fourth often joining the tertiaries Walls and basal 

 expansion naked. Costa3 usually well developed. The transverse 

 dissepiments are few and simple. 



This genus differs from Astrangia chiefly in the deeper calicles, 

 rudimentary and contorted columella, and in the very exsert, sub- 

 entire primary and secondary septa. 



Phyllangia dispersa Verriii. 



Phyliangia dispersa Yerrill, Bulletin Museum of Conip. Zoology, i. p. 47, 1864; Pro- 

 ceedings Boston Soc, vol. x, p. 332, 1866. 



Plate IX, figures 3, :3\ 



Corallites cylindrical or turbinate, very unequal, varying in height 

 from "10 to '40, and in diameter from "20 to "30 of an inch, and either 

 close together or scattered at distances of '30 to "50 of an inch, but 

 connected together by a continuous expansion from the enlarged ba- 

 sal portion of the walls. This is generally rather thin, though some- 

 times forming crusts two or three inches broad, the surface is granulous 

 and the costiB of the walls extend over it in the vicinity of the cor- 

 allites, gradually fading out as they recede. The walls are compact, 

 finely granulous, covered with low, rounded, unequal costje, those 

 corresponding to the principal septa often becoming cristiform and 

 denticulate toward the summit. Calicles deep at center, with con- 

 spicuous, deep interseptal chambers, giving an open appearance. 

 Septa very unequal; the primaries are broad, much exsert (about "lO 

 of an inch), somewhat recurved outwardly, the inner edge usually 

 perpendicular or overarching, the end broadly rounded, sometimes 

 arcuate, entire or minutely denticulate, thin at the inner edge, thick- 

 ened outwardly ; the inner edge usually recedes toward the base, which 



