90 
The abactinal plates on the arms exhibit a differentiation into 
median slightly larger plates, and lateral or intermediate plates. 
The abactinals cease at the level of the last three or four marginals, 
so that these are in contact across the arm (which, Ludwig states, is 
never the case in O. penicillatus). 
I have in the Otago Museum a specimen which was obtained in 
1900, which in form is more nearly pentagonal than that represented 
in Bell’s figure, and more like Ludwig’s figure (pl. v, fig. 6). In it 
the marginals are in a better state of preservation than in the “ Nora 
Niven” specimen, and the marginal tubercles have distinctly this 
pemcilatus arrangement—z.e., a smooth groove is visible between 
contiguous marginals: the tubercles do not interdigitate over this 
groove. The abactinal plates are continued, in three arms, to the 
apex ; in the other two arms the last pair of marginals meet dorsally. 
The measurements in this specimen are R. 33, r. 21; and r.: R. = 
1:1:57. The last feature is characteristic of O. grayt, and the existence 
of only eight marginals on each side is confirmatory, though the other 
two characters might point to penicillatus. 
Locality. East of Otago Heads, 20-40 fathoms (O.U.M.).] 
Remarks.—This little starfish 1s readily distinguished from Asterodon 
miliaris, apart from its smaller size, by the distinctly spinous character 
of the plates, and by the single glassy-tipped dental spine at each 
angle of the mouth. 
The occurrence of this species in our waters is an extremely inter- 
esting geographical fact, as hitherto it has only been found in the 
Magellan Straits, off Tierra del Fuego, and at the Falkland Islands, 
in a depth of from 10 to 105 fathoms. 
Asterodon miliaris, Gray. 
Astrogonium rugosum Hutton, 1872. 
Gnathaster miliaris Farquhar, Trans. N.Z. Inst., xxxix, 1906, p. 126, 
In this paper Farquhar gives the earlier synonymy. 
Stations 15, 16, 22, 26, 29. 
I had, independently of Mr. Farquhar, arrived at the conclusion 
that Hutton’s A. rugoswm is identical with Gray’s species, as a 
result of an examination of the type in the Dominion Museum, which 
Mr. Hamilton, the Director, was good enough to lend me for the pur- 
pose in March, 1907. 
In placing it in the Archasteride instead of the Pentagonasteride 
I follow Bell, Bronn, Delage, and others. In deciding on its title to 
be placed in the genus Asterodon I am influenced by the following 
considerations: This family contains several sub-families, of which 
the Gnathasterine consist of starfishes with well-developed oral angles, 
which may bear one or two dental spines, glassy-tipped and aborally 
directed. There are, according to Delage, five genera: Asterodon, 
Perrier ; Odontaster, Verrill ; Acodontaster, Verrill; Gontodon, Perrier ; 
