102 POLTZOA. 



small, orbicular, those towards the lower part of the branches with a 

 raised, slightly thickened, annular border, which is sometimes produced 

 into an acute angle on one side ; a pore above and below the mouth ; 

 anterior surface marked with smooth reticulated ridges, forming nearly 

 regular diamond-shaped areola? ; posterior surface sulcate, the sulci 

 usually diverging obliquely from an imaginary median line, and finely 

 punctate ; surface between the sulci smooth or sub-granular. 



IDMONEA. 



Polyzoariurn ramose, branches dichotomous or irregularly divided ; 

 free or anastomosing ; mouths of cells disposed in parallel, transverse 

 or oblique, usually alternate, rows on each side of the front of the 

 branches, which are angular or carinate in the middle. 



79. I. giebeliana, Stoliczka, Toy. Novara, Pales., p. 115. Dicho- 

 tomous, branches depressed, anastomosing ; cells irregular, sometimes 

 single, sometimes in series of three or four, and sometimes in clusters 

 of four to eight ; mouth round, raised; both surfaces minutely punctate; 

 branches elliptical. 



PUSTULIPORA. 



Polyzoarium ramose, branches cylindrical, clavate or terete ; com- 

 posed of tubular cells, which open on all sides of the branch. 



80. P. delicatllla, Busk, Crag Polyzoa, p. 108. Dichotoinously 

 branched, occasionally anastomosing ; branches crowded, erect, tapering 

 to fine points, fragile ; composed of loosely aggregated undulating cells 

 which are distinctly ringed. 



Australia(P). 



I refer this species to P. delicatula, Busk, in order to prevent an 

 unnecessary multiplication of names, but I have seen no sufficient 

 description of that species. 



81. P. haastiana, StoliczJea, Voy. Novara, Palce., p. 102. 

 Branches erect, close, anastomosing, in thick masses with the ends 

 truncated to the same spherical surface ; sub-cylindrical ; cells distant, 

 marked with longitudinal lines ; mouth slightly prominent, recurved, 

 sub-orbicular, margin thickened. AVhite. 



Common. 



82. P. proboscid.89, Milne-Edwards. Irregularly branched ; 

 branches spreading, slender; cells numerous, granular; mouths pro- 

 jecting, recurved, slightly contracted. Purplish. 



83. P. porcellanica, sp. nov. Branches slender, spreading, 

 smooth ; cells rather distant, wholly immersed, orifice sub-orbicular, 

 neither raised nor margined ; branches cylindrical, sometimes anasto- 

 mosing. 



Lyall's Bay. 



CINCTIPORA, gen. nov. 



Polyzoarium erect, ramose ; branches dichotomous or irregularly 

 divided, free, cylindrical ; cells immersed ; mouths attached to the 

 stem and to one another, forming circles round it ; cell walls thin, 

 punctured internally. 



