TURBINARI^E TABULATE. 61 



Group VI.— TURBINARI^ TABULATJl. 



TurUmrim in which the carallaform thick, more or less Iwrizonial, dish-like growths icith 

 the margins turned up. Successive growths form flat tiers one ahove amtlier. 



Species 42. Turbinaria reniformis. (PI. XVII. ; PI. XXXII. fig. 14.) 



Description.— QoraWxxm a flat expanse, symmetrically reniform in outline, with margin 

 gently curved upwards ; outer margin slightly wavy, inner slightly notched or lobed. 



Calicles on hemispherical protuberances, apertures circular (2 mm. in diameter), numerous 

 without excessive crowding, septa 16 to 18, mere granular projections from the margin, but 

 descend as thin ridges vertically round a large cylindrical fossa ca. 1 • 5 mm. deep. Columella 

 flat, conspicuous, more coarsely granular than lamellate. Interseptal loculi mere notches in 

 the rough granular margin of the calicle. 



The ccenenchyma granular, round the edges like rusty iron, changing on the under surface 

 to a coarse, and on the upper to a fine echinulation. On the under surface developing marked 

 furrows. 



The type specimen is clearly an old stock expanded upon the remains of former stocks. 

 Two former growths can be made out. The lowest and thickest, though dead and decayed, 

 apparently forming the attachment of the stock to the side of some object. 



The name of the tyi^e refers merely to the accidental form of the outline of the specimen. 



From the method of growth, it is obvious that the corallum must be very massive, it 

 only thins at the growing edge. The actual growing edge is a thin, continuous line of young 

 calicles, forming a ridge below the level of the upper surface of the ccenenchyma, but in a 

 line with that of the lower: this row will eventually bend upwards and a new row will 

 commence below them. The lines of concentrically arranged calicles thus produced soon 

 become irregular and wavy or zigzag, but are nevertheless recognisable. 



There is only one specimen, forming an almost regular kidney- or bean-shaped dish, nearly 

 40 cm. hi longest diameter and 20 across. The dead under surface and former growths are 

 infested by a sponge, closely imitating the coral in the size and appearance of the oscula and 

 in general surface texture and aspect. They might easily be mistaken for portions of the coral 

 which is, as is well known, richly provided with stinging batteries. 



a. Palm Islands, Great Barrier Reef. Saville-Kent Coll. (Type.) 



Species 43. Turbinaria foliosa. (PI. XVIII.; PI. XXXII. fig. 15.) 



Description.— Qox^Wnm a horizontal fan-shaped plate showing radial ridges and pro- 

 tuberances. The new growth spreads horizontally over the old. ilargin tliin, tui-ned neither 

 up nor down. 



Calicles very protuberant, tall thin cones, the lops of whit-h are quite filled up by the 

 apertures. Apertures minute, round (1 • 25 mm.), margin very thin. Septa (12) thin, regular. 



