a General History of the Marine Polyzoa. 125 
tooth on the lower margin ; the rim of the elevated peristome 
set round with about eight spines; the front margin carried 
up into a tooth-lke mucro. Oactum globose, smooth, recum- 
bent. Avicularia none. 
Loc. Off Curtis Island, on Retepora and Flustra dissimilis. 
Mucronella tricuspis, n. sp. 
(Pl. IIL. fig. 1.) 
Zoecia ovate, moderately convex, separated by shallow 
sutures, hyaline, smooth or slightly roughened; orifice trans- 
versely elliptical, three tall spines on the upper margin, in 
front closed in by a screen-like elevation, which in the centre 
rises into a dentate process rounded at the top, and on each 
side of it into a projecting lobe, a furrow down the middle of 
it; on each side of the cell, about halfway down it, a raised 
avicularium, with a slender pointed mandible directed outwards. 
Oecium globose, smooth, silvery, with a projecting rim round 
the opening, the avicularia of the neighbouring cells flanking 
it on each side. 
Loe. Off Curtis Island, on shells &c., very common. 
A very marked and abundant form. I cannot find any 
description of it in the works of Australian writers, though it 
is difficult to believe that it has escaped observation. It is 
not amongst the forms figured by MacGillivray in his work 
on the Victorian Polyzoa. 
Ruyncworora, Hincks. 
Under this name I have constituted a genus* for the recep- 
tion of the remarkable form Lepralia bispinosa of Johnston. 
Amongst Capt. Warren’s dredgings a species occurs which 
has many features in common with the last named, but which 
seems to be distinct. Reserving for the present all questions 
respecting the genus, I shall describe it provisionally as 
Rhynchopora longirostris, n. sp. 
Zoecia pyriform, ventricose above, narrowing off and de- 
pressed towards the base, quincuncially disposed, rather 
coarsely granulated, with a line of perforations round the 
edge ; orifice (primary) transversely elliptical, perfectly 
simple; secondary orifice, formed by the elevation of the 
peristome, subelliptical or irregular in shape and of large 
* Hist. Brit. Mar. Poly. vol. i. p. 385. I am indebted to Miss Agnes 
Crane for pointing out to me that the name Rhynchopora had already been 
appropriated toa genus of Brachiopods; so that a substitute must be found 
for it. 
