1899.] CORALS FROM FUNAFUTI. 51 



seen the ' Challenger ' specimen, and consider this to be the 



same form. 



Previously recorded from south of Papua, off the Ki Islands, 

 depth 140 fathoms ; and Port MoUe, Queensland. 



Family Plexaueib^e. 



EuPLEXAUKA AiiTTiPATHES Klunzinger. (Plate IV. figs. 1, 2.) 



Plexaura antipatJies Klunzinger. 



This specimen, which is in a dried state, is pale fawn in colour. 



The colony is much branched, the branches arising approxi- 

 mately in one plan(i. The branches are given off irregularly; 

 they, in their turn, branch repeatedly, and these branches bear 

 further branches. There are no traces of anastomoses. The 

 basal portions are shghtly flattened, but the terminal twigs are 

 round and thicken shghtly towards the ends. The branches run 

 close together and fairly parallel. 



The polyp-pores are scattered irregularly over the whole surface, 

 and are not raised above the general level except on the terminal 

 twigs, where they are at the summit of slight conical elevations. 

 Thev are about 1 mm. apart. 



The cortex is friable, and somewhat thicker on the twigs than 

 the older parts. It is comparatively smooth ; on the older 

 branches there are slight longitudinal furrows which run somewhat 

 spirally round the stem. The axis is of horn, with scattered 

 particles of calcareous matter ; it is of a dense black colour in the 

 thicker branches. 



The "root" portion of the colony shows a great development 

 of a peculiar skeletal substauce, hard, and looking like stone. 

 It is dull grey in colour, and shows the same furrowings as 

 the cortex of the stem which extended over it. On treating with 

 acid the stony part is dissolved away, leaving a fine network of 

 horny matter in which the CaCOj was contained. 



The grey substance which strengthens the base of attachment 

 is clearly formed independently of the black axis, although it may 

 rightly be regarded as being o'f the same nature. Judging from 

 the dried specimen it is composed of spicules of hme embedded in 

 a horny matrix, no processes of the ccenosarcal canals extending 

 into it, even superficially. It is extremely hard, and breaks with 

 a clean fracture when struck with a hammer. The horny axis, 

 on the other hand, can be cut with a penknife. The_ nature of 

 the horny substance is not determined, but from its insolubility 

 seems similar to the keratin of the axis. It is only rarely seen in 

 specimens of Gorgonacea in Museums, although it is possible that 

 it may be formed at the base of all large Gorgonids when exposed 

 to strong tides. 



In the centre the calcareoi.s 'natter is white and friable, not 

 having assumed the stony, solid appearance of the outer part. 



The basal enlargement is seen also in Plexaura principalis and 

 P. sufruticosa, in the National Collection at South Kensington ; 



