294 THE VOYAGE OF H.M.S. CHALLENGER. 



lat. 7° 3' N., long. 121° 48' E., from a depth of 102 fathoms and on stony and gravelly 

 ground. The third was bought in a dried condition by Dr. Doderlein in Enoshima. 



The transverse diameter of the tolerably thick-walled tubes, which form a dense 

 basket-work, varies between 5 and 7 mm. The oscular openings are frequently some- 

 what contracted on the extremity of the freely projecting, short ends of the tubes. The 

 Japanese specimen shows one irregularly bounded basal plate, which formed a flat 

 expansion on the stony substratum. From this plate arise the thick, partly solid, partly 

 hollow supports of the plexus of tubes. It is probable that these relatively large 

 basal plates have resulted from the confluence of the several basal expansions of the 

 originally independent supports. In the case of the two Challenger specimens, one of 

 which is represented on PL LXXVIII. fig. 1, the basal portion is entirely absent. On 

 the Japanese specimen, as well as on both those from the Philippines, there were numerous 

 small irregularly scattered Actiniae with a diameter varying from 1 to 1*5 mm. 



The dictyonal framework exhibits a tolerably regular structure with predominantly 

 square meshes, smooth or but slightly spinose beams, and scarcely thickened, moderately 

 spinose nodes of intersection (PL LXXVIII. fig. 2). Between the beams of the dictyonal 

 framework small rough oxyhexacts occur in variable abundance, most plentifully in the 

 basal region. They lie freely, or fused with single-rayed parenchymalia. In the latter 

 case the dictyonal framework is, in several regions of the stock, further strengthened by 

 the tolerably abundant occurrence of a second kind of parenchymalia, viz., medium-sized 

 oxyhexasters with short principal rays, each bearing twci long moderately divergent 

 terminals (PL LXXVII. fig. 6). Besides these, numerous uncinates occur, which are 

 remarkable in their structure, and to some extent also in their disposition. For while the 

 uncinates are otherwise almost always disposed at right angles to the bounding surfaces, 

 in this case many of them not only penetrate the wall transversely, but occur abundantly 

 disposed obliquely or parallel to the bounding surfaces. Forms so directed are much 

 longer than the others. Both exhibit a somewhat marked flattening on both sides. The 

 somewhat thickly apposed pointed barbs are not uniformly distributed all round, but 

 sometimes occur on two slightly spiral longitudinal rows on the nari'ow edges of the 

 uncinate, while the two flatter surfaces remain smooth. 



The pentacts of the dermal skeleton vary in size, and bear rough cylindrical rays of 

 medium length, which are simply rounded ofi" at the extremity. The four tangentials, 

 which are tolerably straight, are not disposed quite at right angles to the proximal ray, 

 but more or less inclined towards it. A knob-like protuberance represents the abortive 

 distal ray. 



Besides these pentacts there are numerous scopute, represented by two difierent 

 forms. The less frequent form is provided with four knobbed terminal prongs, whUe 

 the much more numerous second type bears, on a knob-like thickening of the inferiorly 

 pointed stalk, two to four slightly divergent barbs, which are rather strongly develoj^ed 



