1869.] DR. J. D. MACDONALD ON A NEW CIRRIPED. 441 
Moreton Bay *, I found them beset with beautiful little pink-tinted 
barnacles, having a vitreons-looking capitulum, about one-eighth of 
an inch in length, with shelly depositions bearing an important re- 
lation to the rudimentary valves of Dichelaspis and Conchoderma. 
In general form, however, and even in many details of their anatomy, 
these little parasites are perfect miniatures of Lepas anatifera, their 
most striking character being that the valves, which are semitrans- 
parent in the greater part of their extent, are distinctly in articu- 
lation with each other, or closely approximate (see Plate XXXIII. 
fig. 3). 
The peduncle is of considerable length, and cylindrical, though 
tapering a little towards the capitulum (Plate XX XIII. figs. 1 and 2). 
It is, moreover, so transparent as to exhibit, under a low power, its 
outer circular and inner longitudinal layer of muscular fibres, with 
the contained tubular structure and pink-coloured ova. When more 
matured these latter reach the hack part of the cavity enclosed by 
the valves, where they become arranged in a single leaf-like layer, 
which, adapting itself to the curvature of the posterior and lateral 
valves, receives the body of the animal in its concavity. In this 
single expansion the union of two ovigerous lamellze is indicated by 
a central notch in its inferior border (fig. 2, 6 & c). To an ordi- 
nary observer the oral organs would present a great similarity to 
those of Lepas, but they appear to be somewhat more prolonged, so 
as to form a kind of proboscis. 
In the capitulum the valves are five, approximate, corneous, and 
strengthened by the ‘deposit of shelly matter, as above mentioned ; 
besides which they are marked with distinct lines or increments of 
growth, and dotted with minute points, indicating at least a pseudo- 
eell-structure (Plate XXXIII. fig. 3). These lines of growth are 
obtusely angular in the scuta (4), but rather semicircular in the terga 
(c) and carina (d). The centre of development is posterior and basal 
in the carina, anterior and basal in the scuta, and posterior and sub- 
apical in the terga. 
The shelly supporting piece of the scuta consists of a long and 
fusiform occludent segment, connected with a rudimentary basal one, 
and an intervening oblique ray directed towards the middle of the 
carina. The shelly part of the terga is subapical and narrowly 
crescentic, with the convexity near the dorsal border. Finally, the 
shelly framework of the carina consists of a narrow mid-rib extend- 
ing only to the base of the terga posteriorly, but bifurcated at the 
proximal end, where each limb skirts the base of its own moiety. 
In the occludent margin of the capitulum the lines of growth 
(Plate XXXIV. 6) increase in length and thickness from before 
backwards. 
The parts of the mouth more particularly considered afford the 
following characters :— 
The labrum (Plate XXXIV. c) is protuberant or bullate, its an- 
gular edge supporting a row of fine conical tubercles. 
* This species is also abundant at Sydney, and amongst the islands of the 
South-western Pacific. 
