2. Scleronephthya flexilis Thomson and Simpson, var. compacta n. (Plate XV, Fig. n ; 
Plate XXII, Fig. 7). 
Stat. 164. i°42 / .5 S., I30°47'.5E. 32 M. Sand, small stones and shells. 15 Ex. 
Stat. 279. Roma-island. 36 M. Mud and sand. 1 Ex. 
Numerous colonies of a brownish or cream colour from Station 164, with a very short 
sterile stem, and a few short main branches which bear numerous hummocks densely covered 
with polyps. Two colonies had the following dimensions: (a) 4cm. in height, 3cm. in breadth; 
( 6 ) 6 cm. in height, 2.5 cm. in breadth. 
The body of the polyp is supported by irregular lines of curved spindles, and this 
armature leads at the top to eight points, consisting of a pair or two pairs of chevron spindles. 
Intervening between the points and the longitudinals there is sometimes a single or double 
collaret of horizontals. The horizontals vary considerably in number and distinctness according 
to the state of contraction; they cannot be regarded as a “crown” in the sense in which this 
term is used in Axifera; they belong to the polyp-stalk more than to the anthocodia. Within 
the points are seen the heavily spiculated dorsal surfaces of the retracted tentacles. The canal 
walls contain heavy warty spindles up to 2 mm. in length. 
The spiculation agrees generally with that of A. flexilis , but there is a much larger 
number of bow-shaped forms, both slender and stout. The differences do not appear to us to 
be of more than varietal value. 
A small colony from Station 279 shows the same mode of growth, and the same armature 
of the polyp, but the surface of the'stem is smooth, without the wrinkles so commonly found 
in this species. The spiculation shows the same types of spindle, but there is a smaller number 
of the tuberculate bow types; and the delicate spindles from the polyps are somewhat smoother. 
W e are inclined to regard Scleronephthya flexilis Thomson and Simpson as a somewhat 
variable species, difficult to deal with when the colonies are young and the canal-walls cannot 
be called thick, and no trace of central fusion is to be seen. In larger colonies, however, the 
central fusion is sometimes very distinct. 
Yet the specimens are Nephthyids without trace of supporting bundle; the polyps arise 
singly in thick clusters on the short branches; they show a characteristic armature of warty straight 
and curved spindles; the warts are sometimes compound, sometimes simple and relatively longer. 
Contracted colonies of this species bear a strong superficial resemblance to A. pitstulosa. 
Previously recorded from E. coast of Sumatra. 
3. Scleronephthya pustidosa Wright and Studer. 
For description see: WRIGHT and STUDER, Challenger Report, 1889, p. 229, 2 figs. 
Stat. 
47 - 
Stat. 
50. 
Stat. 
144. 
Stat. 
164. 
Stat. 
257. 
Stat. 
277. 
Stat. 
310. 
Stat. 
3 V- 
Bay of Bima. 55 M. Mud with patches of fine coral sand. 5 Ex. 
Labuan Badjo, Flores. Up to 40 M. Mud, sand and shells. 1 Ex. 
Damar-island. 45 M. Coral bottom and Lithothamnion. 1 Ex. 
i°42'-5 S., I30°47 / .5E. 32 M. Sand, small stones and shells. 1 Ex. 
Duroa-strait, Kei-islands. Up to 52 M. Coral. 2 Ex. 
Dammer-island. 45 M. Sand, white and black mixed. 3 Ex. 
8° 30'S., H9°7 / .5E. 73 M. Sand with few pieces of dead coral. 4 Ex. 
Sailus Besar, Paternoster islands. Up to 36 M. Coral and Lithothamnion. 2 Ex. 
