ALCYONTTDiE. 257 



specimens. The remaining three specimens, which appear to be very much older, are 

 extremely hard, irregular, mushroom-shaped masses, with convex capitula thinning 

 out towards the edges, set with short frequently laterally compressed lobes, usually 

 arranged in radiating ridges. 



DO 



The lolied specimen from the Maldive Islands appears to be intermediate in form 

 and age between the cup-shaped specimens and the hard, irregular, mushroom-shaped 

 specimens from Ceylon. 



The complete specimen is 47 millims. high and the capitulum measures 92 milium 

 by 80 millims. across its surface. The stalk is short, broad, laterally compressed and 

 constricted in the middle. It is 25 millims. high and has a diameter at the base of 

 80 millims by 40 millims. A few of the lobes are branched. Their average height 

 near the middle is 10 millims. All the specimens give off a peculiar pungent odour 

 even in spirit. 



Only autozooids are present in this species. They are fairly numerous on the 

 margin of the colony and on the lobes, but are few in number in the furrows between 

 the lobes. All the specimens are hard and granular, owing to the enormous spicules 

 which are very thickly set and extremely abundant. 



This species has hitherto only been recorded from the Maldive Islands. 



Alcyoniuin ceylonicum, n. sp. Plate II., figs. 10 to 12. 



A single complete colony was taken from the reef at Galle. 



The specimen has an irregularly ridged capitulum and is creamy white in colour. 

 The colony is 60 millims. high and the capitulum measures 75 millims. by 55 millims. 

 across its surface. 



It is tough and fleshy in consistency, slightly softer and more fleshy in the middle 

 than near the surface, where the spicules are much more abundant. 



The Zooids are extremely small and are very numerous (13 or 14 to the centimetre), 

 they are uniformly distributed over the entire upper surface of the capitulum. 

 Measurements across the partially expanded crown of tentacles average 0'6 millim. 

 None of the zooids are completely expanded. The apertures of contracted zooids are 

 so minute as to be almost imperceptible without the aid of a lens. As the tentacles 

 are only partially expanded, it is difficult to distinguish their pinnate character. 

 They are extremely short, the longest measuring only 0"16 millim. in length. The 

 stomodasum averages 0'5 millim. in length and has a moderately large siphonoglyph. 



The mesenteries are small, and the musculature only feebly developed. As in 

 many other tropical forms, the dorsal mesenteries have extremely long and well 

 developed filaments, but the ventral mesenteries have no filaments (Plate II., fig. 11, 

 r.ni.). As in several other instances (Pratt, 1904, in the press), this reduction of the 

 digestive surface is accompanied by an abundance of zoochlorelke in the superficial 

 endodermal tissues. 



The Spicules are similar in form (fig. 12) to those of A. pachyclados, but are 



2 L 



