38 
Journal of the 
theca? parallel with the pinna in their longest diameter, crossed in 
in the hack part by a fold or constriction vertical to the pinna ; 
aperture nearly parallel with the pinna, each side forming a broad 
sub-angular lobe, everted ; a long, nearly erect tooth in front. 
Hydrothecal inter nodes smaller at the proximal end, with two- 
deep constrictions extending almost round them, one transverse, 
opposite the constriction of the hydrotheca, the other directed 
obliquely forwards from the base of the lateral sarcotheca?, 
generally a third midway between them. Mesial sarcotheca rising 
partly from the pinna, but mainly from the arched front of the 
liydrotheca, to which its base is adnate as far forward as the 
aperture; projecting forward at an angle of about 70° with the 
pinna, the free part about equal in length to the shorter diameter 
of the hydrotheca ; narrowed near the lateral orifice, and somewhat 
swollen between that and the terminal one, with an orifice 
communicating with the cavity of the hydrotheca immediately 
below the external lateral aperture; base in front produced 
downwards into a short septum or ridge in the liydrotheca. 
Lateral sarcotheca? somewhat similar to the mesial in form, rising 
considerably above the margin of the liydrotheca, to which they 
are adnate; divergent, directed upwards and slightly forwards, 
with two apertures, lateral and terminal. Cauline sarcotheca?, 
two on the stem at the base of each pinna, conical, with lateral 
and terminal apertures united. 
Gonangial pinme usually two or three on a shoot, recurved, 
bearing about fifteen or twenty pairs of alternate pinnules, each 
springing from a short internode, and furnished with two lateral 
series of sarcotheca?, resembling the mesial ones of the liydrotheca? ; 
sarcotheca? opposite or sub-alternate, the two proximal ones on 
the distal side of each pinnule without corresponding ones on the 
opposite side; pinnules jointed above the proximal sarcotheca, 
which is larger than the others and often bifid. Two conical 
sarcotheca? on the pinna at the base of each pinnule. The two 
series of pinnules slightly arched, meeting at the points, and 
forming an open corbula, surrounding the delicate ovate gonotheca?. 
A single liydrotheca on eacli gonangial pinna below the corbula. 
Colour, light brown. Ilab., Queenscliff; Aldinga, S.A. ? 
(Mr. Smeaton). 
