15 



8. Stylaster multiplex sp. n. Plate I, figs. 11 and 12. 



Stat. 94. 5 1 1'.2 N., U9°35'.4E. Sulu lis. 450 M. 1 colony. 



Stat. 177 (?). 2°24'.5 S., I29°38'.5E. N. of Ceram. 1633 M. Scveral fragments. 



The branches of this species are flabellate, but they are closely set one above the 

 other, as is well shown by the very complete specimen obtained from Stat. 94 (Fig. 11). None 

 of the branches anastomo.se. The height of the colony is 35 mm. the breadth about 40 mm. 

 the diameter of the base of the stem, before it spreads out to attach itself to the substratum, 

 4 mm. The young branches are very zigzag in their course. The colour is a yellowish white, 

 the surface smooth except for dotted, irregular longitudinal striations. The cyclosystems are 

 slightly inclined towards one surface. 5. multiplex is a transition stage between those species 

 that have a complete cyclosystem (i. e. with no dactylozooids atrophied) turned to the side, 

 such as 5". öclla, and those like S. tiliatus which have the cyclosystems on one surface only. 

 For further discussion of this point see p. 17. In S. multiplex the cyclosystems are about 1,5 

 by o, 8 mm. diameter and two successive cyclosystems on the same side of the stem are 2,8 mm. 

 apart. The gastropore is deep, the septa wide. The ampullae are developed in ones, twos, 

 threes, or fours, close to a cyclosystem on the anterior or posterior surface of the flabellum. 



This species may be defined : 



Hydrophytum subflabellate ; cyclosystems complete, slightly inclined towards one surface; 

 gastropore deep. 



9. Stylaster minimus sp. n. Plate II, figs. 13 and 14. 



Stat. 150. o°6' N., I29°7'.2 E. Djilolo Passage. 1089 M. One small fragment. 



Only one very small fragment of this delicate deep sea coral was found. So far as can 

 be observed in a piece of such small size it is regularly flabellate and the branches do not 

 anastomose. The height of this fragment is about 10 mm., the diameter of the thickest part 

 of the stem 1 mm. The colour is white. The surface appears to be quite smooth in spirit, 

 but when it has been calcined it is seen to be slightly rough. The cyclosystems are all turned 

 towards one surface of the flabellum; their edges are slightly crenate and they are 1 mm. 

 by 0,8 mm. in diameter. The gastropore is fairly deep, but is not curved down the stem; the 

 gastrostyle is therefore visible from the exterior, though it is not placed at the centre of the 

 base of the gastropore but further down towards the base of the stem. The septa are wedge- 

 shaped; the interseptal spaces are narrow. The cyclosystems are 1 — 4 mm. apart. A branch 

 arises in the axil of each cyclosystem. No ampullae are visible. 



This species closely resembles S. tiliatus in external characters (except for the difference 

 in size) and Stylaster (Stenohelia) profundus, but may be readily distinguished from both by 

 the comparative shallowness of the gastropore (cp. Moseley 1. c. Plate XII, fig. 4). S. minimus 

 is still more delicate than the type specimens of S. profundus in the British Museum. 



This species may be defined : 



Hydrophytum flabellate (or subfiabellate ?) delicate ; surface smooth ; cyclosystems all 

 directed towards one surface; gastropore not very deep or curved far down the stem. 



