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



which are flesh-coloured, contain little spiny needles, which are simply spindle-shaped or 

 approach more or less nearly the shape of a club ; they are straight or curved. They 

 are arranged in eight tentacular groups, each group composed of two rows of spicules 

 arranged en chevron, and finally continued into the base of the tentacles. Here the 

 spicules are usually curved. Length to breadth — 0"58 by 0"05 ; 0'25 by 0"025 ; 0"3 

 by 0-03 ; 0-2 by 0-03 ; 0-21 by 0-025 ; O'lS by 0-04 mm. 



The walls of the inner canals are not very thin, and are firm, whereby the colony 

 acquires a fairly tough consistence. 



The colour of the stem is yellow and of the little heads flesh-red. 



Habitat. — Zebu Reef, Philippine Islands. 



Sioongodes spicata, n. sp. (PI. XXXVId. figs, la, Ih). 



The colony forms an irregularly branched lobose mass, which rises from a basal 

 expansion growing over a stone. 



One can distinguish a number of thicker main stems, which sometimes branch 

 dichotomously and rise up from the base in diverse directions. These are covered with 

 cylindrical, warty to finger-shaped, lateral twigs, which come oS" from the stem some- 

 times at obtuse angles and sometimes vertically, and are thickly covered with little polyp 

 heads ; they also often bear lateral processes covered with polyps, or again give oS spike- 

 like twigs. The form of these twigs most nearly recalls that of the flower-heads of 

 Phyteuma spicata. The length of the stems reaches 115, 75, and 50 mm. Their 

 thickness at the base, 28, 29, and 17 mm. The length of the ears, 12 to 16 mm.; their 

 thickness 5 to 8 mm. 



The consistence of the stem and branches is leathery. 



The polyp heads occur partly scattered or united in groups on the stem and larger 

 branches, and partly on the cylincbical terminal twigs, which they completely cover. 

 Each head is surmounted by a stout bundle of spicules, which projects for a distance of 

 1 to 2 mm., and gives to the heads a spiny prickly appearance. 



The spicules of the stem and branches are large spindles. They are horizontally 

 placed, but not so closely as not to leave occasional gaps, which are filled up by the 

 naked leathery tissue. 



The spicules are large, spindle-shaped, often bent, and more blunted at oae end than 

 at the other, sometimes almost club-shaped, thickly covered with fine spines. 



Their size reaches 1-5 by O'l ; I'O by 0*12 ; r3 by 0-08 mm. 



The polyp heads are surmounted by bundles of rough spiny spicules, which are united 

 together to the number of six. Their length reaches 1'2 to 3 mm., and their spines are 

 more strongly developed than those of the stem spicules. In the heads the spicules are 

 not so regularly arranged as in the preceding species. They are spindle-shaped, and 



