502 THE STOLONIFERA AND ALCYONACEA 



The tentacular operculum and the collaret agree with Wright and Studer's 

 description (28). The contracted polyps are I'o mm. in length and l^S mm. in diameter. 



The spicules agree in form and size with the description of those of the type 

 specimen. The branches are yellow and the polyp heads red in colour. 



Habitat. Talili Bay, New Britain. 



Previously recorded from the Hyalunema ground, 345 fms., Japan. The occurrence 

 of this species in shallow water off New Britain and in deep water on the Hyalo- 

 nema ground is a very noteworthy fact in distribution. 



Family. Alcyonidae. 



Wright and Studer (28, p. 238) are of opinion that only those fleshy Alcyonids 

 found in the cold and temperate sea should be included in the genus Alcyonium, 

 those found in the tropical seas being referred to the genus Lohularia. 



As these authors have pointed out (28, p. xxi) there is great difficulty in 

 distinguishing Alcyonium from Savigny's genus Lohularia. It is true that many of 

 the tropical species have large spicules which cause the cortex to have a leathery 

 consistency when compared with the cortex of the species of the cold and temperate 

 seas ; but there appear to us to be many reasons why this feature should not be 

 regarded as one of generic importance. In this collection there are three specimens 

 which are so remarkably similar to the European species Alcyonium glomeratum that 

 it would be absurd to place them in a distinct genus. We agree therefore with 

 Klunzinger and others in not recognising the genus Lohularia. 



A word of explanation may be made here as to the use of the term stalk in 

 the following pages. 



In the genus Sarcophytuin the colony assumes a form which has not inaptly 

 been compared to that of a mushroom ; there is indeed a well-niarked differentiation 

 of the upper part or head from the lower supporting part or stalk. The important 

 morphological difference between the two parts is that the expansible portions of the 

 polyps, called for the sake of brevity polyp heads, protrude from the capitidum but 

 do not protrude from the stalk. In some genera of Alcyonidae, such as Alcyonium 

 and Nephthya, the head and stalk are not so sharply differentiated as in Sarcophytum, 

 and in the literature of the subject several terras such as " barren part " or " sterile 

 portion" have been employed for what is morphologically equivalent to the stalk of 

 Sarcophytum. In our opinion atiy expression which implies barrenness or sterility in 

 the part named is misleading and consequently we use throughout the term " stalk " 

 for the part of the colony which does not bear polyp heads. 



13. Alcyonium polydactylum, Klunzinger. 



The colony has apparently been split in two and only one half is in the bottle. 



It is 85 mm. high ; the stem is 55 mm. long by 35 mm. wide, the head is 

 30 mm. high by 70 mm. broad and is much divided. 



There are five main branches, each of which bears several branchlets on wliich 

 the short, obtuse, somewhat finger-like processes are crowded. 



