Zoology.'] NATURAL HISTORY OF VICTORIA. \_Pohjzoa. 



Plate 185, Fig. 1. 

 AMATHIA BICORNIS (Tenison- Woods). 



[Genus AMATHIA (Lamouroux) = SEKIALARIA (Lamakck). (Sub-kingdom Mollusca. 

 Class Polyzoa. Order Iiifundibulata. Sub-order Ctenostomata. Family Vesiculariidas. ) 



Gen. Char. — Zoarinm radicate, erect or creeping, with free filiform dichotomous branches. 

 Zooecia sub-tubular, connate, in two parallel rows, continuous or in distinct groups which are 

 placed on one or two sides of the branches or wound spirally, partially or wholly, round them.] 



Description. — Zooecia of moderate height, deeply hollowed above (when dry), 

 with a long- hollow process on each side at the summit, arranged in close spiral 

 clusters of about two whirls, the basal clear parts of the internodes being- about the 

 same length as the clusters. 



References. — Serialaria spiralis, Tenison-Woods, Trans. Roy. Soc. N. S. 

 Wales, 1877, p. 84; Amathia bicornis, Tenison-Woods, Tr. Roy. Soc. Vict., June, 

 1879. 



Port Phillip Heads. 



Forms dense masses of a brownish colour, the largest I have 

 being about an inch and a half in each direction. The close 

 double spiral clusters, separated by clear portions of the branches 

 of about the same length, with the peculiar hollow processes from 

 the summits of the zooecia, are sufficiently distinctive. 



Explanation of FiGtrKEs. 



.Plate 185. — Fig. 1, part of specimen, natural size. Fig. la, small portion of same, 

 magnified. Fig. 26, two zooecia, more highly magnified. 



Plate 185, Fig. 2. 



AMATHIA SPIRALIS (Lamx). 



Description. — Zoaiium formiag large tufts of dichotomously divided branches. 

 Zooecia very long and narrow, arranged in a continuous spiral round the branches, 

 interrupted only at the bifurcations. 



Reference. — Lamouroux, Hist, des Polyp. Corall. Flex., p. 161, pi. iv., fig. 2. 



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