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



globular, but when dried becomes wrinkled and has a depression 

 round the upper edge and sides, omng to the shrivelling of the 

 delicate outer envelope, M'hich seems to be separated by some 

 distance from the inner part. 



In the Challenger Poljzoa, Mr. Busk describes eight species 

 of Farciminaria, and sajs that "the genus may be regarded 

 emphatically as abyssal ; the mean depth at which the species 

 hei-e enumerated occurred being not less than 1,500 to 1,600 

 fathoms, or fi*om 450 to 2,750 fathoms." F. Brasiliensis was, 

 however, found at from 32 to 400 fathoms. The three species 

 here recorded were dredged from a depth of 10 to 15 fathoms, so 

 that the genus cannot by any means be considered as abyssal, a 

 fact which Mr. Busk would no doubt have ascertained if the 

 dredgiugs of the Challengei^ had not been almost exclusively 

 confined to deeper waters. 



Explanation of Figubes, 



Plate 158. — Fig. 5, branch of specimen, natural size. Fig. 5a, portion of same, magnified, 

 showing a shrunken ooecium. Fig. 5a, another portion, in outline. 



Plate 158, Figs. 6-8. 

 BRACEBRIDGIA PYRIFORMIS (Busk, sp.). 



[Genus BRACEBRIDGIA (McG.). (Sub-kingdom MoUusca. Class Polyzoa. Order 

 Infundibiilata. Sub-order Cheilostomata. Family Escharidse.) 



Gen. CAar.— Zoarium encrusting, or erect and bilaminate. Zooecia distinct, entire ; mouth 

 sub-circular, with an internal denticle ; peristome raised, thick, vicarious avicularia on the free 

 margins of the branches, the triangular mandibles with a projecting articular process at each 

 lower angle.] 



Description. — Zoarium usually consisting- of flat bilaminate branches with 

 lateral lobes, the branches more or less twisted on themselves. Zooecia .pyriform, 

 separated by deep grooves ; mouth sub-circular, with a broad denticle internally, and 

 occasionally a small apiculate process on the lower lip ; an elevated ridge round the 

 mouth, the two sides meeting- below the lower lip and continuing- down the zooecium 

 as a central elevation ; surface smooth or minutely granular. On the free edge ot 

 the lobate branches is a single row of aviculiferous cells. 



Reference. — Mucronella pyriformis, Busk, Challenger Polyzoa, pt. i., p. 155, 

 pi. XX., fig. 5; Bracehridgia pyriformis, MacGillivray, Tr. Roy. Soc. Vict, Nov. 

 looo. 



Vol. II.— Decade XVI.— 2*. [ 219 ] 



