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



In the pol}'3)-beariug portion of the stem occur, in addition to these spicules, 

 irreouhxrly scattered spindles ; these are continued into the branch(:S and twigS, where 

 they are longitudinally placed, and where also they are closely packed, and give rise to 

 the brittle consistency of the twigs. In the peduncles of the polyp heads one spindle 

 is especially developed ; this spindle projects above the head, which appears to lie 

 laterally upon it. These spicules are slender, spindle-shaped, slightly curved, either 

 simply or /^shaped, and covered all over with sharp spines; size, 0'8 by 0"05 mm.; 07 

 by 0-05 mm.; 1-5 by 0*05 mm.; 0*9 by 0-04 mm.; 3-0 by 0-08 mm.; 3-8 by O'lS mm.; 

 4"0 by 0"1 mm. 



The spicules which project above the heads measure up to 4"0 by 0"25 mm. The 

 polyp heads show at their base a number of peripherally disposed spindles, from which 

 eight project, sticking up from the base above the margin like teeth. They are 

 supported at their origin by smaller spindles which converge towards them. These 

 spicules are thickened at the base, pointed towards the outside, and covered with 

 outwardly directed spines resembling the teeth of a saw ; size, 0"9 by 0'07 mm. There 

 are also developed at the base of the tentacles, two long spicules converging upwards ; 

 these measure up to 1 mm. in length, and when the tentacles are folded together are 

 themselves laid tos;ether over the mouth. The tentacles themselves are covered with 

 small, curved, scale-like, transversely arranged spicules, which attain a size of 0"15 by 

 0-017 mm. 



The colour of the colony, stem, branches, twigs, and polyp peduncles, is white ; that 

 of the polyp heads orange-red. 



Habitat— Station 192, off the Ki Islands; lat. 5° 49' 15" S., long. 132° 14' 15" K; 

 depth, 140 fathoms ; bottom, blue mud. 



Spongodes cervicornis, n. sp. (PI. XXXVId. figs. 2a, 2h). 



This species closely resembles the preceding one in habit. The main stem is attached 



to the substratum, on which it grows by means of a broad foot-plate. Already close 



above the base it gives off single larger branches, which like the main stem give off at 



right angles on all sides sparsely ramified secondary branches, on whose terminal twigs the 



polyps are placed on long peduncles. The ramifications in this case are, nevertheless, 



somewhat different from that of the preceding species, in that the polyps come off, not 



only from the ends of the twigs, but also from the sides, and are surmounted by long 



spicules. The twigs are less rigid, rather soft and yielding. The entire colony is flabby 



and shrulvlike from the presence of numerous larger branches. 



Height of one colony, ...... 100 ram. 



Diameter of the main stem near the base, . . . 18 ,, 



Length of one of the larger branches, . . . . iO ,, 



Length of the smaller secondary branches, .... 8-12 ,, 



