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Also (Mus. Zool., Cambridge) : — 



Torres Straits, 195, A.C. HADDON Collection, Reg. Feb. 24, 1898. 

 Queensland, Port Denison, Miss E. C. JELLY, Reg. May 24, 1895. 



Oueensland, Port Denison and Holborn Island, Australian Museum, Sydney, Reg. Oct. 23, 

 1S99 (from remains of the Collection described by Prof. W. A. Haswell). 



Zoarium consisting of a few coarse, irregularly arranged branches which bifurcate rather 

 seldom and do not keep in one plane. Zöoecia few and large, often with greatly produced 

 peristomes. Ovicell occurring at a bifurcation, variable in form, but extending some way up 

 one of the branches thus formed. Ooeciostome terminal, meeting the rest of the ovicell at an 

 angle, and when fully developed with a transversely elongated ooeciopore, bounded by well 

 developed lips. 



The present species is distinguished from the other forms dredged by the 'Siboga' by 

 its more robust zooecia, and by the characters of its ovicell. lts growth is very irregular, the 

 branches not keeping in the same plane, and varying in thickness. The largest colony examined 

 (239. A.) is about 20 mm. in greatest length, and consists of two main lobes, which diverge 

 from one another close to the base of the colony at an angle of nearly 180 . Not more than 

 three or four bifurcations are present in any branch, so that the colony does not attain much 

 complexity of growth. 



The zooecia, while maintaining a practical uniformity in their sectional area, vary much 

 in other respects. The peristome is either short or long; and it may continue the direction of 

 the proximal part of the zooecium in a uniform curve, or it may leave that part at a distinct 

 angle. The direction of its growth may be uniform or irregular, an alteration of the curve 

 being frequently visible at some point in its length. It is frequently marked by circular Unes of 

 orowth. As will be seen from fig. 12, the number of zooecia present in any transverse section 

 of a branch is small compared with that found in some other species. This character depends, 

 ho wever, on the degree of vigour in the growth of the branches, some of which may be 

 slenderer than in the portion figured; while in other parts, particularly in the region immediately 

 preceding a bifurcation, the number of zooecia present at the same level may be increased. 



The ovicell of the specimen figured (fig. 1 2) commences at a bifurcation and extends 

 along only one of the branches so formed. This fertile branch shortly bifurcates again, although 

 one of the branches has been broken off. With the first bifurcation placed in the plane of the 

 drawing the ovicell is seen from the side; but if the bifurcation which occurs at about the 

 middle of the ovicell had been in that plane it is obvious that the ovicell would have been 

 seen in frontal view. This is a consideration which has to be borne in mind in comparing this 

 specimens with others. At the point where the second bifurcation was formed there has been 

 an interruption in the continuity of the growth of the ovicell, as is shown by the persistence 

 of part of the margin of the growing end of the branch as the ridge which is seen crossing 

 the ovicell. The remainder of the roof of the ovicell has been formeel by a calcareous lamina 

 developed slightly within this edge. Another sudden change in the direction of growth is 

 indicated by a kind of collar present near the base of the ooeciostome. 



The ooeciostome is a wide tube which leaves the ovicell at its distal end; and it is 



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