ZooIogy.-\ NATURAL HISTORY OF VICTORIA. [Po/^joa. 



The branches are coloui-less, very clear, and glassy. The 

 zooecia are of moderate height, of nearly uniform size, although 

 usually rather shorter distally, and are arranged in an open spiral 

 forming a nearly complete turn. The figure, taken from a dried 

 specimen, does not show the characters so satisfactorily as one 

 preserved in spirit, and I shall therefore give a fresh one when 

 figuring the remaining species of the genus. 



* Explanation of Figures. 



Plate 185. — Fig. 3, portion of specimen, natural size. Fig. 3a, portion of same, magnified. 



Plate 185, Fig. 4. 

 AMATHIA INARMATA (McG.). 



Description. — Zooecia arranged in unilateral biserial g^roups of 4-9 pairs, 

 occupying- nearly the whole leng-th of the internodes which are slightly arcuate, of 

 moderate heig;ht, slightly diminishing; towards the distal extremity. 



Reference,— P. H. MacGillivray, Tr. Roy. Soc. Vict., Nov., 1886. 



Port Phillip Heads. 



This is considered by Kirkpatrick (Ann. and Mag. Nat. Hist., 

 July, 1888) to be the A. biseriata of Krauss. I have not seen 

 Krauss's work (Corallinen und Zoophyten der Sudsee), and 

 therefore cannot say whether this identification is correct. South 

 African specimens, however, which I have received from Dr. 

 Pergens as A. biseriata are certainly diflferent. 



The extent of internode occupied by the clusters varies, these 

 sometimes extending almost the whole length, at other times a 

 considerable portion at the base being bare. 



Explanation of FionKES. 

 Plate 185. — Fig. 4, portion of specimen, natural size. Fig. 4a, part of same, magnified. 



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