50 
AUSTRALASIAN ANTARCTIC EXPEDITION. 
able from Lagisca by the absence of the prostomial frontal lobes or “ peaks the dorsal 
chaetse are generally smooth or very feebly striated ; the ventrals unidentate in even in 
the young. Therefore, he believes that to unite the two genera would be premature. 
But is the statement of differences altogether correct ? For Elders describes the 
presence of these “ peaks ” to two species, Hermadion ambiguum and H . molluscum 
(1897, p. 16); they are present in H. rouchi. It is true that these peaks are absent in 
the type species, H. magalhaensis Kinberg, as well as in his H. longicirratum and in 
H. kergudensis McIntosh (1885), which according to Fauvel are synonymous. On the 
other hand, although typically present in Lagisca, they may be absent (see L. jeffreysii 
McIntosh, for instance). It seems as if there ought to be a great deal of shifting of these 
species from one genus to the other, if we accept Fauvel’s dictum. 
As to the dorsal chsetse, it appears that in young stages of H. rouchi, at any rate, 
as well as in other species, the dorsal chsetse do have striations, that is fine pectinated 
frills or combs, whereas in the older chaetas, the longer ones, they are less distinctly 
marked. It may be that this is due to wearing away of the frills owing to use. And a 
similar explanation may perhaps be given of the absence of a sub-apical tooth in the 
ventral chsetse. For although this is generally absent, yet it does occur in the shorter 
younger chaetae, or in others its place is taken by a “ step,” in this position. 
It appears then that the distinctions between the two genera Lagisca and Herma¬ 
dion do not exist. They are identical. 
A further question has been raised as to whether or not there is any real distinction 
between the genera Hermadion and Harnotluc. If we review the various oligomeric 
forms, it appears that Harmotlioe has its dorsum entirely covered by the elytra ; that 
none of the posterior segments remain uncovered, or at most only two or three. Whereas 
in Hermadion, several, up to a dozen or more, are exposed in large forms. It is true 
that Willey has ascribed to Harmotlioe spinosa an individual which he regards as a 
variety and calls “ lagiscoides ,” partly because of the conical tubercles on the elytra, 
and this one individual has 6 naked segments at the hinder end. But more information 
is needed to convince me that the individual is a variety of Harmotlioe spinosa. 
Yet, because of this variety, Willey proposed an addition to the generic diagnosis 
of Harmothce, which would eliminate the only remaining constant difference between 
it and Hermadion, and so comes to the conclusion that all three genera are synonymous. 
For the present, I am of opinion that it would be well to retain the distinction 
between Harmotlioe and Hermadion. 
localities .— 
Commonwealth Bay, Station 1 , 350-400 fathoms (six, colourless). 
Station 10, 325 fathoms (one juvenile, colourless). 
Station 12, 110 fathoms (one juvenile, coloured). 
No data (one coloured and one uncoloured, juvenile). 
Distribution.— Marguerite Bay, lie Adelaide (Gravier), Kaiser Wilhelm II Land 
(Ehlers). 
