Zoology.-] NATURAL HISTORY OF VICTORIA. [Polyzoa. 



References. — H. divaricala. Busk, Brit. Mus. Cat. Mar. Pol., pt. i., p. 30, 

 pi. xviii., fij^s. 3, 4- ; Hincks, Brit. Mar. Pol., p. 288, pi. xliv., fig's. 1-4 ; and pi. i., 

 fig. 2 ; //. palagonica, Busk, Brit. Mus. Cat. Slar. Pol., pt. i., p. 30, pi. xvii., fig-. 1. 



Hobson's Bay and Port Phillip Heads, on algse, shells, and 

 zoophytes. Usually occurs in slender, silvery, dendritic colonies, 

 the zooecia being connected by short, rather thick fibres, originating 

 from the summits or sides of the zooecia in irresrular numbers 

 (usually one or two) and occasionally branching from other tubes. 

 The tubes or fibres are smooth or annulated. Their lena:th varies 

 very much, Ijeing sometimes considerably longer than the zooecia, . 

 at other times shoi-t and scarcely apparent, the result being in 

 the so-called variety conferta almost as close an aggregation as 

 in a Lepralia^ but with a tendency to branch off at the edges. The 

 mouth is expanded above, narrowed below, and has usually a 

 shallow sinus in the lower lip. The ooecium is round or globular, 

 the zooecium which it surmounts usually smaller than the normal, 

 and frequently originating directly from the side of another. The 

 ooecium also frequently has a round boss or umbo in front. The 

 roughly annulated form is Busk's H. patagonica. 



Explanation of Figdkes. 



Plate 18T. — Fig. 8, portion of a specimen with the zooecia transversely striated and 

 carinate. Fig. 8a, zooecium and ocecium from the same. Fig. 9, portion of another specimen, 

 with zooecia mostly annulated and those bearing ooecia arising from the sides of ordinary zooecia, 

 connecting fibres of considerable length. 



Plate 187, Figs. 10-13. 

 HIPPOTHOA DISTANS (McG.). 



Description. — Zooecia connected by very long, slender threads, small, 

 elongated, smooth, finely striated, or faintly annulated; anterior surface rounded 

 or carinate; mouth subcircular, or wider above and narrowing downward^ into a 

 shallow sinu.t, peristome distinctly thickened. Ooecia globular, terminal, smooth, 

 or umbonate. 



References. — H. distans, P. H. MacGillivray, Tr. Roy. Soc. Vict., 1868; 

 H.jiageUum, Hincks, Brit. Mar. Pol., p. 293, pi. xliv., figs. 5—7; Busk, Chall. 

 Pol., pt. i., p. 4, pi. xxxiii., fig. 7. 



Yoii. II.— Dbcadb XIS.-2Z. [ 321 ] 



