REPORT ON THE ASTEROIDEA. 261 
which I propose the generic name of Gnathaster. 1 have also retained as genera several 
of the sections relegated by Perrier to subgeneric rank under Pentagonaster, viz, Cal- 
haster, Calliderma, Astrogonium, Stellaster, and Ogmaster (= Dorigona). Though the 
characters upon which these genera are based exhibit many transitional stages, it appears 
to me too sweeping a measure to merge them in one generic term. ‘hat the differences 
should be slight and the cases of transition frequent in a large and widely distributed 
family such as the Pentagonasteride is not surprising. As, however, the morphological 
characters of the forms in question are in my opinion sufficient to warrant recognition, it 
seems to me that to lose the record of their significance by an unnecessary exercise of 
comprehensiveness would be a mistake. 
Astrogonium and Dorigona, it should be mentioned, have recently been restored by 
Perrier’ himself as generic names, but the sense in which they have been applied appears 
to me to be inadmissible, for reasons which I shall give in detail. 
I have substituted the generic name Ogmaster for that of Dorigona. The starfish 
described by Gray’ in 1866 under the name of Dorigona reevesw is the same species as 
that previously described by Miiller and Troschel* in 1842 under the name of Gonzodiscus 
capella. In 1865 von Martens* placed this form in a subgenus to which he gave the 
name Ogmaster, ranking it under G‘oniaster. The claim of this form to generic recogni- 
tion has since been admitted, and it follows in my opinion that the name of the starfish in 
question should therefore be Ogmaster capella (M. & T.), von Martens. (Its synonyma are 
Dorigona reeves, Gray, and Goniaster miilleri, Liitken ; but not Goniaster (Stellaster) 
miillerc of von Martens.) The Goniaster (Stellaster) miillerc of von Martens is a true 
Stellaster, which is so nearly allied to Stellaster childreni that | am unable to distinguish 
it, and I am therefore constrained to consider Gonzaster miilleri as a synonym of that 
species. Both Liitken and Perrier have been in error in regarding von Martens’ form as 
identical with the species described by Gray as Dorigona reevesit. 
A second form which has been referred to the genus Dorigona is the starfish described 
by MGbius® under the name of Astrogoniwm longimanum. This form is totally distinct 
from Gray’s form, and merits, in my opinion, an independent generic recognition. | 
therefore propose for it the name of Jconaster. It is characterised by the naked abactinal 
plates margined by very remarkable valve-like plates, by the character of the adambulacral 
1 Ann. Sct. Nat. (Zool.), 1885, t. xix., Art. No. 8, p. 30. I would here take the opportunity of mentioning 
that the sheets of this Report which treat of the Porcellanasteride and Archasteride were printed off before 
I had seen this last mentioned important memoir by Prof. Perrier, and I was consequently unable to refer to 
the species described therein, as I otherwise should have done. 
2 Synop. Spec. Starfish Brit. Mus., London, 1866, p. 7, pl. 7, figs 3, 3a. 
3 System der Asteriden, 1842, p. 61. 
_ 4 Ueb. Ostasiat. Echin., Archiv f. Naturg., Jahrg. xxxi., Bd, i. p. 359. 
5 Neue Seesterne des Hamburger und Kieler Museums, 1859, p. 7, taf. i., figs. 5, 6. (Abhandl. a. d. 
Gebiete Naturw. hrsg. v. d. naturwiss, Verein, Hamburg, Bd. iv. Abth. 2, 1860.) 
