Mr. W. K. FisUei- on Asteroidea. 167 



receiitlf describecl, in an important paper* on Australian 

 echinoderms a species called Mediaiter 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 

 tlie dorsal integument in a line parallel to the margin of the 

 ray. In Nectria monacoMtha tliese tuEts are 4 or 5 in number 

 on either side of each ray, and extend as far as the fourth 

 superomarglnal 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 tiie superomarginals as far as the sixth 

 superomarginal plate, or a trifle o^'er one-third the length of 

 ray measured on side. In Jl/ediasler the gonads are in series, 

 but do not extend so far as in Nectria ocellata. Tiiis distri- 

 bution of the gonads is a good ciiaracter to separate Rosaster, 

 Mediaster, and Nectria from Geramaster 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^ papulge. Nectria has 

 supplementary internal actinal intermediate plates. 



The intermarginal papulte 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 oceUifera they are 

 absent. The subfamily Nectriiuse, Perrier, which I resusci- 

 tated on the basis of these papulae, should therefore be 

 discarded. If Verrill's subfamily Mediasterin^ is recognized, 

 it would seem that the older name of Perrier's should be 

 used for it, because Nectria and Mediaster are so close. 



NyynpJiaster, Sladen. — In liis diagnosis of the genus in tlie 

 " Narrative of tiie 'Challenger' Expedition," lb85, p. 612, 

 Sladen mentioned no species, so that the genus really dates 

 from 1889 (' Challenger ' Asteroidea, p. 294). Here no type 

 is designated. Tiie following species are described: — sym-^ 

 holicus, bipunctus, proteiitus, albidus^ hasilicus. In 1^99, 



* " Report on the Sea-Lilies, Brittle-Stars, and Sea-Urchins obtained 

 by the F.I.S. 'Endeavour' on the Coasts of Queensland, New South 

 \Vales, Tasmania, Victoria, South Australia, and Western Australia," 

 123 pp., 42 pis. Sydney, June 2, 1916. 



