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



cavities canal-lilve and elongated, penetrating tlie entire stock and found both in the twigs 

 and stems. Only four of the septa enter into the elongated gastral cavities, namely those 

 which bear the sexual organs and the long, narrow, mesenterial ridges. Sexual j)roducts 

 contained within the elongated gastral tubes of the smallest branches." 



" Genus Siphonogorgia, KoUiker, with much connective tissue in the sarcosoma, 

 especially around the gastral tubes. Polyp calyces with slightly developed calicular 

 opercula." 



Siphonogorgia mirabilis, described l.)y Klunzinger {loc. cit.) from the Red Sea, 

 exhibits still more markedly the habit of the Gorgonidte, but Siphonogorgia squarrosa, 

 Kolliker and Studer, while retaining the essential characters of the genus, strongly recalls 

 the Nephthyidse. The canal-system is analogous, as is also the system of narrow nutrient 

 canals ramifying between the polyp tubes. The relationship with the Nephthyidse is still 

 more easily effected through the new genus Chironephthya, so that it appears proper to 

 give up the isolated subfamily of the Siphonogorgiacea^, and to place the genus under the 

 family of the Nephthyidse. The diagnosis of KoUiker's subfamily then remains as the 

 diagnosis of the genus ; the subfamily Siphonogorginge here created being understood in 

 a much wider sense. 



Siphonogorgia godeffroyi, Kolliker. 



A specimen found only in fragments, which appear to belong to a young colony, 

 may be referred to this species, so thoroughly described by Kolliker. It consists of a 

 main stem from whose upper portion short branches come off on all sides. The barren 

 portion forms half of the stem. The branches are covered with small, appressed polyp- 

 calyces, within which the tentacles are sunk. In that the branches and twigs are still 

 very short, and the greater portion of the same is occupied by polyps, the habit of the 

 colony differs somewhat from that of the specimen described liy Kolliker. But since 

 the finer structure, spicules, canal-system, colour, &c., agree, we may refer the present 

 specimen to the same species. 



Habitat. — Station 232, Hyalonema-gYonnd, Japan ; depth, 345 fathoms. 



Siphonogorgia kbllikeri, n. sp. (PI. XXIV. fig. 2). 



An upright, ramified colony, whose main stem gives off short, bl\int branches on two 

 sides at angles of about 80 degrees. These branches are not further ramified, and they 

 bear at the end a group of two or three polyps. Polyps also occur arranged spirally on 

 the stem and brandies. The polyps are placed obliquely to their su^jport, the mouth 

 being directed towards the end of the branches. They possess a tentacular operculum 

 composed of spicules. The stem and branches are somewhat flattened in the plane of 



