TURBINARI^ CRATERIFORMES. 33 



towards the axis of the cup. Cup irregularly contorted. The graceful stalk characteristic of 

 young specimens thickens in such a manner that the cup stands like an inverted cone. 



CaUcles not crowded, projecting as short, blunt cones, 2 mm. high. The aperture 

 occupies the whole top of the cone, oval (2 mm. maximum long diameter). Septa (14 to 18) 

 granular, irregular, continuing the ridges of the co^nencliyma, projecting (seen from above) 

 beyond the half-radius circle, bending round gradually from the margin to descend vertically, 

 limiting a clear, small elliptical fossa ; a well-marked columella rises as a directive plate, which 

 is thickened in the centre with granules. The interseptal loculi are long gashes in the margin, 

 very irregularly bounded peripherally by the crenenchyma, often continued into the furrows. 



The surface of the coenenchyma on the inside is marked by a very pronounced ridge-and- 

 furrow system, the latter being still further deepened by the long slit-like pores opening in 

 their depths. On the outside, the ridge-aud-furrow system is well marked, especially towards 

 the base. 



This coral is named after the curiously woolly appearance of the surface of the 

 coenenchyma within the cup, due to the dark pores seen within the furrows. There are three 

 specimens, one an extremely delicate and perfect cup 6 cm. across and 5 cm. high (PI. Y.). 

 A second is about the same size, but snapped from its stem, and with the cup flattened into a 

 fan shape. The largest specimen is a cup 15 cm. across, showing a peculiar contortion which 

 may be typical, inasmuch as this method of folding will explain the origin of the 

 remarkable T. contorta (cf. p. 74) from an original cup. 



a. Singapore. H. N. Ridley, Esq. (Type.) 



h, c. [Young cups, one showing section of stalk.] Singapore. H. X. Ridley, Esq. 



Species 10. Turbinaria aurantiaca. (I'l. IV. ; PI. XXXI. fig. 9.) 



Description. — Corallum a cup, showing slight foldings ; margin not very thin, but 

 wrinkled externally. 



Calicles not crowded, and not typically projecting. Aperture circular (diameter 1 • 5 mm. 

 and less), the ring-like margin rising very slightly above the coenenchyma. Septa (18-20) 

 project but very little from the margin, and descend vertically, bounding a large and deep 

 fossa. Columella compact, spongy, slightly convex. Interseptal loculi not sharply defined 

 peripherally. 



Coenenchyma finely granular inside, outside either granular or very delicately striate. 



This species has been established to contain five specimens which appear to be allied, in 

 spite of considerable differences. The largest specimen is remarkable for a method of growth 

 and multiplication of the individual polyps, which, if not pathological, ought to constitute it 

 a separate species. There is sufficient evidence, however, to show that the specimen has 

 grown under abnormal conilitions, owing to what appear to have been depositions of sediment 

 within and on the margin of the cup. The " abnormal " growths referred to deserve detailed 

 description, as they occur in all stages. The distal margin of a calicle rises like a hood, 



F 



