i8 



WRIGHT and STUDER (1889) give a somewhat more detailed description of the genus 

 as follows : 



"The colony is upright and branched; the stem and branches are compressed, irregular 

 in section; the completely retractile polyps occur in a row within a groove along the sharp 

 edge of the branches. The medullary mass forms an axis of spicules. It is close, but -brittle 

 in texture, not penetrated by, but surrounded by, longitudinal canals". 



The only modification of this definition that the present writer would suggest is the 

 omission of the last phrase. While it is true that the axis in many of the smaller branches is 

 notpenetrated by the canals, it is also true that the large stem of the Siboga specimen about 

 to be described is penetrated by perfectly evident, indeed conspicuous, water-vascular canals. 



The type species of this genus is Iciligorgia schrammi Duchassaing. The only other 

 known species is Iciligorgia orientalis Ridley. 



i. Iciligorgia orientalis Ridley. (Plate IV, figs, i, ia). 



Iciligorgia orientalis Ridley. Zoological Collections of H. M. S. "Alert", 1884, p. 351. 



Stat. 273. Anchorage off Pulu Jedan, East coast of Aru Islands. 13 meters. Sand and shells. 

 Stat. 315. Anchorage east of Sailus Besar, Paternoster Islands. Up to 36 meters. Coral and 

 Lithothamnion. 



Colony incomplete, flabellate, profusely branched, 31 cm. in height and about 25 cm. 

 in spread. Base missing. The main stem is irregular in section proximally, flattened higher up 

 where it has a section of 8 X 12 mm. It gives off a branch 4.8 cm. from its proximal end. 

 Almost immediately above this it forks into two main portions each of which again forks. 

 Beyond this the branching is irregular, but there is a distinct tendency toward a unilateral 

 arrangement of the ultimate twigs, and branchings of the 4 th and 5 th orders are attained. The 

 ultimate twigs are long and slender, sometimes being as much as 1 7 cm. long. All of the 

 branches and branchlets are more or less flattened, one of the main branches having a cross 

 section of 1 1 X 7 cm. and an ultimate twig a section or 3.5 mm. X 2 mm - 



The branches have a lateral sharply compressed edge or border, very strongly marked 

 proximally and becoming practically obliterated on the distal parts. In the narrow edges of 

 these ridges or borders there is a sharply impressed groove, like a knife cut, running along 

 the sharp edges of all of the branches and twigs, although it is often practically obliterated 

 by the closing of the adjacent coenenchyma over the groove. In this groove the polyps are set 

 in a single row on each side of the branches. 



There are no calyces, except a few irregularly and sparsely scattered over isolated 

 localities on what appears to be the back of the colony. These are low rounded verrucae, 

 sometimes round, sometimes oval, and showing indications of eight lobes around the margins. 

 They can hardly be considered as normal. The polyps are completely retractile. There are a 

 few curved spindles on the basal parts of the tentacles which show a tendency toward an en 

 chevron arrangement. 



A cross section of the stem shows a thin coenenchyma filled mainly with oval coarsely 



