526 MR. E. W. SHANN ON 



these, rather than to create a new genus from the observation of 

 a single specimen. 



"Wright and Studer (1889, p. xxxvi) give the following de- 

 finition of the genus Wrightella : — " The bi-anches and twigs are 

 compressed ; the projecting polyp calyces occur especially on the 

 sides. In the cortex there are foliaceous clubs. There are no 

 nutritive canals in the axis." The specimen fulfils all these 

 conditions. 



The single main stem arises abruptly from a strong reticulate 

 base (fig. 9). The base, which is broken at the edges, measures 

 15 mm. in diametei-, and the gaps in its meshes average 1 mm. 

 in diameter. The colony is 120 mm. in height and 45 mm. in 

 breadth (some of the lateral branches are broken, so it is probable 

 that the true breadth exceeded 45 mm.). The branching of the 

 colony is dichotomous, and takes place at the swollen nodes. The 

 nodes are less prominent in the distal branches. All the branching 

 takes place in one plane; the terminal twigs are markedly flattened 

 in the plane of branching. Anastomosis of the upper branches 

 takes place at infrequent intervals. The nodes near the base are 

 globular, having a diameter of 4 mm. ; the internodes in this 

 region are circular in section, their diameter ig 2*5 mm., which is 

 slightly exceeded by their length. The internodes beyond the 

 lowest three become more elongated and show an average length 

 of 10 mm. The terminal twigs are only 1 mm. wide. The 

 varrucfe, which measure "75 X '75 mm., are not densely crowded, 

 and show a tendency to ari^ange themselves on the lateral aspects 

 even of many of the lower branches, but more especially in the 

 tei^minal twigs. Both cortex and vert-ucse ai-e yellow in colour. 

 The axis is white, and is not traversed by nutrient canals. 



The precise locality is not recorded, but, like the other speci- 

 mens in this collection, it was taken in shallow water near 

 Singapore. 



The spicules attaiil all manner of shapes (fig. 15); they 

 are quite colourlessj The foliaceous clubs characteristic of the 

 genus WrigJdella are present in large numbers, and show the 

 following range in measuremeht : length by breadth -27 x '12 mm., 

 •15 X "06 mm. ; handles of clubs "0!^ mm. in diameter. Numerous 

 spindles occur, some are foliaceotis and measure -27 X "07 mm., 

 •20x"08 mm>, -12 X "06 mm.; others are spiny, the spines fre- 

 quently being confined to the central region, and measure 

 •22X-05 mm., '17x-03 mm., •12X-03 mm. A few stellate 

 forms are found which have a diameter of •10-'15 mm. Minute 

 scales a,bound ; thfey measure '05 js< '025, '036 X "030 mm., 

 •028 X -014 mm. 



Liiei'uturei 



1870. Gray, J. E.— Cs^t. Lithophytes Brit. Mus. p. 31. 



1900* HiCKSON, S. J., and Hiles, Isa L. — "The Stolonifera and 



Alcyonacea collected by Dr. Willey in ISTew Britain. 



etc." AVilley's Zodi. Kesidts, pt. iv> pp* 493^508. 



