FKOM THE INDIAN AND PACIFIC OCEANS. 37 



of outer wall : elongate warty spindles of very varying length, some large opaque 

 spicules of a conspicuous creamy-yellow colour reaching 3 - 35 mm. in length, others 

 smaller, numerous, some yellow and some red. Spicules of partition-walls : typical small 

 thorny spindles. Polyp-spicules : crown with about six transverse rows ; points with 

 three to five spicules, somewhat irregularly arranged en chevron, of which one is generally 

 larger than the others. Tentacles with scattered small warty spicules. 



Colour. Stem and branches deep crimson ; terminal twigs have a few large conspicuous 

 cream-coloured spicules, and are shaded from crimson to buff-yellow, terminating in 

 yellow calices. Folyps crimson : the contrast between the colour of calyx and polyp 

 gives a striking effect, and each polyp appears to be set in a yellow ring. 



Sab. Admiralty Islands. 



Chironephthya gracilis, sp. n. (PI. 5. fig. 40 ; PI. 6. fig. 60.) 



Colony 14 cm. long, sterile stalk 6 cm. Stem divides into two main branches directed 

 vertically upwards, from which several short very slender branches arise. Polyps borne 

 on all branches, those on main branches sessile and single, those on terminal twigs in 

 groups and generally on short stalks. Spicules of outer wall : long slender spindles 

 with few small warts, of various sizes. Spicules of partition-walls : minute thorny 

 spicules of typical form and size. Polyp-spicules : crown with about five transverse 

 rows ; points with three to five spicules arranged en chevron, larger than those of crown 

 and with more pronounced warts. Tentacle-spicules comparatively large. 



Colour. Stem and branches deep red ; polyps bright orange. 



Sab. Admiralty Islands. 



Chironephthya retractilis, sp. n. (PL 6. fig. 55.) 



Colony 5 cm. long, consisting of one main erect branch and two short branches given 

 off at about 175 cm. from base. Polyps borne all round stem, completely retractile 

 within calyx, which projects from stem, and closes over polyp by all the spicules of the 

 calyx converging together in a point and not folding over as in a Siphonogorgia. The 

 polyps contract in the same way, and the result of this converging of spicules into a 

 point gives the effect of a number of sharp thorns projecting from the stem. Spicules 

 of outer wall : warty spindles of varying size, some curved, mostly straight. Spicules 

 of partition-walls : typical small thorny spicules. Polyp-spicules : crown with about five 

 transverse rows ; points with four spicules arranged en chevron. 



Colour. Stem and branches cream, with crimson-purple polyps. 



Sab. Admiralty Islands. 



Genus Siphonogorgia. 



Siphonogorgia pustulosa (Studer). (PL 6. fig. 65.) 



Several branches 3 to 4 cm. long, straight, unbranched, and presumably belonging to 

 the same colony. Polyps borne all over branches, completely retractile within calyx, 

 which bulges out from stem. Spicules of outer walls : elongate spindles, beset with 



