62 FOSSIL ASTEROIDEA. 
were previously borne (see Pl. XII, fig. 3e). A small entrenched pedicellaria may 
be present on an occasional plate here and there. 
Dimensions.—The example figured on Pl. XII, fig. 3 a,has a major radius of 
about 30 mm.,and a minor radius of about 28mm. The length of the side is about 
36mm. The thickness of the margin is about 10 mm. In the specimen given on 
Pl. XV, fig. 4a, the major radius measures 21 mm., and the minor radius 19 mm. 
approximately. The length of the side is about 25 mm. 
Locality and Stratigraphical Position.—This species is a characteristic Upper 
Chalk form. The majority of examples are from Kent and Sussex. A fine series 
from Bromley is preserved in the British Museum. 
History.—This species was referred to by Dr. Mantell under the name of 
Goniaster regularis. The specific name was, however, already preoccupied—at 
least in literature—for an existing starfish; and although the latter is not now 
recognisable, no doubt can possibly exist that Mantell’s fossil species is certainly 
a different thing from the starfish to which Linck gave the name of Pentagonaster 
reguilaris. 
Forbes was the first to describe the species under the name of Goniaster 
(Goniodiscus) Hunteri, and his type-specimen, which is figured in Dixon’s ‘ Geology 
and Fossils of the Tertiary and Cretaceous Formations of Sussex,’ pl. xxi, fig. 1, 
formed part of John Hunter’s Collection, now preserved in the Museum of the 
Royal College of Surgeons. The examples illustrated in the present work are all 
preserved in the British Museum. 
Variation.—There are at least two well-preserved examples in the collection of 
the British Museum which I consider to be varieties of this species. They are 
characterised by the presence of only four supero-marginal plates on each side of 
the disk, exclusive of the odd terminal plates, as against six plates in typical 
examples. Beyond this difference in number and the relatively greater length of 
the supero-marginal plates in proportion to their breadth, I can indicate no 
character worthy of being noted which would distinguish the examples in question 
from the typical form of Mitraster Hunteri. The specimens under notice measure 
35 mm. and 30 mm. in diameter (R-+ 7) respectively. Both are from the Upper 
Chalk, one from near Bromley, the other being only labelled ‘‘ Kent.” Figures 
of the first-mentioned are given on Pl. IX, figs. 3a—3e. 
