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



y-sliaiiecl ; colourless. Their lengtli reaches 4 to 6 mm., with a thickness of 0"43 ; 0'4 ; 

 0"3 mm. They are continued up the twigs and peduncles of the polyp heads, where 

 they take on a red colour, or are coloured half red and half white. The spindles which 

 overtop the head are mostly red, nearly straight, and measure 2 to 3 mm. in length. 

 Besides the large spindles there are also numerous smaller ones, mostly slender and 

 slightly curved; measuring 1 mm. in length by 0"067 mm. in breadth; 0"3 mm. in 

 length by 0'05 mm. in breadth. These spicules give to the branches and twigs a hard, 

 brittle consistence. 



The pol5q3 heads, whose peduncles are absolutely encrusted with thick spindles, are like- 

 wise armed with spicules. These stand vertically on the base of the polyp, and surround 

 the heads radially up to a point above the bases of the tentacles. They are spiny spindles, 

 with sharp, rigid spines. Sometimes the spindles are blunted above and provided 

 with several spines at the end ; or they may be club-shaped at the end with one or two 

 spiny processes. Between the longer spindles occur also shorter curved spindles. The 

 colour of these is generally that of yellow ochre, or red. Size 0*8 by 0'07 mm.; 0"67 by 

 0-05 mm.; 055 by 0055 mm.; 0-54 by 01 mm. At the club-shaped end; 0'3 by O'OG mm.; 

 0-3 by 0-05 mm. 



The colour of the colony varies much in different parts. The barren trunk appears 

 dark purple ; the stem and branches white. The polyp-umbels in the lower portion of 

 the head are yellow, for the spicules of the polyp heads are here self-coloured. In the 

 upper portion they are dark brownish-red and yellowish. The spicules of the polyp 

 peduncles are purple, those of the heads yellow. 



Habitat. — Torres Strait ; depth, 8 to 10 fathoms. 



Spongodes florida (Esper). 



Spongodes florida, Gray, Proc. Zool. Soc. Lond., 1862, p. 27, pi. iv. figs. 1-4; no7i Spongodes 

 celosia, Less.; nee Spiongodes celosia, var. arhorescens, Dana. 



The fragment in the collection is the upper part of a colony. Gray's description 

 with the help of the figure leaves no doubt as to the identity of the species. The twigs 

 are arranged in umbels and bear bundles of from four to ten polyps, which are only 

 slightly overtopped, each by a large spicule, and are hence almost terminal. 



The white polyp heads are covered with spicules, which form eight groups. Each 

 group is composed of two rows of spicules converging towards the base of the tentacles, 

 and also produced up along the tentacles. The stem and branches contain large spicules 

 of a dark red colour, which are irregularly scattered, leaving naked spaces of soft, 

 leathery outer covering, these are slightly curved spindles covered with spines, which reach 

 up to 4 mm. in length. In the twigs the spicules are more thickly crowded and arranged 

 longitudinally ; as they are also in the peduncles of the polyp heads. Here they are 



