. An account of the alcyonarians collected by the Royal Indian marine survey ship Investigator in the Indian Ocean. Alcyonaria. 17 Nephthya tenuispina, n. sp. Several small but complete colonies attached to pieces of rock, the largest is 3 cm. in liei<;lit. Kioni a si)rea(ling base, 1"8 cm. in diameter, the main portion arises, but this soon gives origin to several long, sliglitlv tapering lobes. These diverge in all directions, some even growing downwards. Polyp-bearing lobes occur all over these secondary branches. A cross-section through one of the larger lobes presents a radiate st
. An account of the alcyonarians collected by the Royal Indian marine survey ship Investigator in the Indian Ocean. Alcyonaria. 17 Nephthya tenuispina, n. sp. Several small but complete colonies attached to pieces of rock, the largest is 3 cm. in liei<;lit. Kioni a si)rea(ling base, 1"8 cm. in diameter, the main portion arises, but this soon gives origin to several long, sliglitlv tapering lobes. These diverge in all directions, some even growing downwards. Polyp-bearing lobes occur all over these secondary branches. A cross-section through one of the larger lobes presents a radiate structure, the canal walls passing from the centre to the circumferenc^e, but this becomes in the older portions by the development of smaller canals towards the periphery. The outer wall is tough and rigid and is densely filled with long spiny S[)indles. The polyiJs are borne on catkin-like out- growths of the larger lobes, but on the main stem they occur in groups separated by considerable intervals—seldom singly. The surface of the whole colony is covered with long, straight or curved spindles, generally arranged in groui)s and disposed longitudinally. On the smaller lobes, where the polyps are more crowded, the arrangement is much more irregu- lar, but here also the grouping is a marked feature. The polyps are almost 2 mm. in length, the stalk being slightly over 1 nun. The " StUtz- biindel" consists of about six long thick spindles, grouped into a sheaf, projecting for a considerable beyond the origin of the body of the Fig. 8. Nephthya 1 ^ —The top of two branches, 1 ^I* enlarged about eight times. The polyp stands at right angles to the stalk and is directed towards the colony, but when the tentacles are fully retracted the oral part projects downwards. Spicules longitudinally arranged cover the whole surface, but there is a hint of eight groups at the base of the tentacles. The spicules are straight and curved, spiny and w
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