Mr. W. K. Fisher on Asteroidea. 167 
recently described, in an important paper * on Australian 
echinoderms a species called Mediaster monacanthus which he 
considers to stand between the Goniasterid genera Mediaster 
and Nectria. I have had the privilege of dissecting a speci- 
men of this species, and it seems to me to belong unquestionably 
to Nectria. 
In Nectria the gonads form 4 or 5 to 9 tufts attached to 
the dorsal integument in a line parallel to the margin of the 
ray. In Nectria monacantha these tufts are 4 or 5 in number 
on either side of each ray, and extend as far as the fourth 
superomarginal plate. In Nectria ocellata (Lamarck) the 
gonads form 9 tufts, beginning with two good-sized ones 
next to the rather solid interbrachial septum, and they extend 
in a series close to the superomarginals as far as the sixth 
superomarginal plate, or a trifle over one-third the length of 
ray measured on side. In Mediaster the gonads are in series, 
but do not extend so far as in Nectria ocellata. This distri- 
bution of the gonads is a good character to separate Rosaster, 
Mediaster, and Nectria from Ceramaster and Nymphaster. 
Nectria may be distinguished from Mediaster by its 
calcified interbrachial septa (these being entirely membranous 
in Mediaster), by the conspicuously larger, fewer, more widely 
spaced, tabulate abactinal plates, and by the relatively large, 
triangular, papular areas of the disk, with upwards of 10 or 
even more (as high as 18 in ocellata) papule. Nectria has 
supplementary internal actinal intermediate plates. - 
The intermarginal papule which I described in ‘ North 
Pacific Asteroidea,’ p. 164, in a species of Nectria from 
Victoria are not characteristic of all species, nor apparently 
of all specimens even, of ocellata, while in ocellifera they are 
absent. The subfamily Nectriinee, Perrier, which I resusci- 
tated on the basis of these papule, should therefore be 
discarded. If Verrill’s subfamily Mediasterine is recognized, 
it would seem that the older name of Perrier’s should be 
used for it, because Nectria and Mediaster are so close. 
Nymphaster, Sladen.—In his diagnosis of the genus in the 
** Narrative of the ‘Challenger’ Expedition,” 1885, p. 612, 
Sladen mentioned no species, so that the genus really dates 
from 1889 (‘ Challenger’ Asteroidea, p. 294). Here no type 
is designated. The following species are described :—sym- 
bolicus, bipunctus, protentus, albidus, basilicus. In 1899, 
* “Report on the Sea-Lilies, Brittle-Stars, and Sea-Urchins obtained 
by the F.L.S. ‘Endeavour’ on the Coasts of Queensland, New South 
Wales, Tasmania, Victoria, South Australia, and Western Australia,” 
123 pp., 42 pls. Sydney, June 2, 1916. 
