Ill 



Y-shaped spici;los are modified forms of a branched spindle, and that one or 

 more of the arms may themselves be branched, and that they differ in appear- 

 ance from the three-rayed forms where the origin of the rays is distinct. The 

 spindles vary from 016 to 24 mm. in length and from 0"048 to 021 mm. in 

 breadth ; the Y-shaped spicules measure up to 1'2 mm., the three-rayed average 

 about 0"4 mm., and the four-rayed average about 0"9 mm. in length. 



(A) In the stalk there are straight or curved spindles, clubs, Y-shaped, 

 three- and four-rayed spicules and numerous irregular forms either slightly 

 spindle-shaped or tending more to a globular shape. All are covered with 

 large, pointed spines. The spindles vary from 016 to I'l mm. in length and 

 from 0"048 to 013 mm. in breadth ; the Y-shaped forms often reach a length of 

 over 1 mm. and the three- and four-rayed forms vary from 016 to 08 mm. in 

 length. 



Canal- wall spicules : (a) In the stem the spicules are a few thick spindles 

 with very few small simple spines on the surface, and a number of smooth, 

 flat, striated forms either rod-shaped with blunt teeth on the edge or three- 

 rayed. The spindles vary in length from 0"64 to 1"6 mm. and in breadth from 

 0-08 to 0-19 mm. 



{/)) In the stalk the spicules are short, thick spindles, three-rayed forms 

 with short thick rays, and numerous small, smooth, striated forms with blunt 

 teeth on the edges. The spindles and three-rayed forms have a number of 

 large prominent spines on the surface. The spindles vary from 0"32 to 0"8 mm. 

 in length and from 0*11 to 0*14 mm. in breadth, and the smooth, striated forms 

 vary from 0048 to 016 mm. in length and from 0'016 to 0*08 mm. in breadth. 



Colour — The stem, stalk and branches are white ; in the upper part of the 

 polyparium the polyp-stalks are usually deep red, in the lower part they are 

 white, while in a peculiar band which runs in a curve from the base of the 

 polyparium to the tip, they are faint red ; the polyp-spicules white ; the 

 tentacles semi-transparent. 



Locality ; Nicobars (F. Stoliczka). 



Dendronephthya rubeola, Henderson. 



To this species is referred a complete specimen measuring 5 7 cm. in height 

 and 4 '2 cm. in greatest breadth. It is characterised by the loose, open arrange- 

 ment of the polyparium, and the contrast between the white polyps and the 

 deep red branches. 



The stalk is 3 cm. long, much shrivelled, and marked by a number of 

 longitudinal grooves and ridges. It is thick at the base, where it gives off a 

 few stolons, and gradually tapers upwards ; it is granular in appearance, 

 leathery in texture and tough, and has its upper part hidden by reflexed 

 flattened branches. 



