General History of the Marine Polyzoa. 165 
Euthyris obtecta, n. sp. (Pl. VII. fig. 3.) 
Zoarium much branched dichotomously; habit rather 
strageling, the segments tall, narrow, not expanded upwards, 
somewhat rounded at the extremities, with a smooth border 
along the edge. Zoawcia on one surface only, quincuncial, 
subrectangular, margins not conspicuous ; front wall smooth 
and shining, depressed below, rising towards the orifice, 
overspread by a membranous covering, which forms a flat 
uniform roofing over the zoarium ; orifice of the ordinary cells 
suborbicular, with the lower margin flattened, surrounded by 
a chitinous rim and closed by a solid operculum; distributed 
amongst the ordinary zocecia are occasional cells which are 
broader and have a larger orifice, elongated transversely, 
narrow between the upper and lower margins, and slightly 
curved inwards below. Avieularia none. Occtum (?). 
Height of specimen about 34 inches. 
Loc. North Australia (Miss Jelly). 
Two points are worthy of notice in this species—the con- 
tinuous membrane which overspreads the surface of the 
zoarium, concealing the true cell-wall, and the larger zocecia, 
with modified orifice, which occur in some number amongst 
the ordinary cells. The latter may be subservient in some 
way to the function of reproduction, though we have no direct 
evidence on the point; similarly modified cells have been 
noticed in other cases. The epitheca also occurs in many 
species belonging to very different families. 
Family Myriozoide (part.), Smitt. 
ScH1zoPoRELLA, Hincks. 
Schizoporella conservata, Waters. (Pl. VII. fig. 2.) 
This species, which has been described by Waters from 
Tertiary beds in South-west Victoria, occurs in Mr. Wilson’s 
dredgings from Port Phillip Heads. As the recent specimen 
differs a good deal in superficial character from the fossil form, 
I have given a figure of a few of the cells. Mr. Waters de- 
seribes the surface of the zocecium as smooth; in Mr. Wil- 
son’s specimen it is strongly areolated round the margin and 
reticulate in the centre. ‘The avicularia, which are numerous, 
are of the lanceclate type; the mandible is long and slender 
————— 
Victoria, December 1881. I have already (f Annals’ for July 1880) di- 
rected attention to the structural peculiarities of this group as probably 
supplying the basis of a new genus, and am glad to find that this view is 
supported by Mr. MacGillivray’s authority. 
