Sladen — Echinodermata from the 8.W. Coast of Ireland. 693 
several rather larger plates than those in the central region gene- 
rally. 
The madreporiform body, which is small and snhoval in form, is 
situated nearer the centre by about its own diameter than midway 
between that point and the margin. Its surface is marked with 
rather coarse irregularly convoluted striations. On its adcentral side 
is a single large basal plate larger than the madreporite itself, and a 
similar large basal plate is present in each of the other interradial 
areas, in a corresponding position, and larger than any of the other 
abactinal plates. 
After the foregoing description was written, and the drawings to 
illustrate it had been made on stone, I found a larger example of the 
species at the bottom of a tin, which had unfortunately escaped my 
notice previously. This specimen measures E. = 54 mm. ; r = 31 mm. 
There are eleven supero-marginal plates, counting from the median 
interradial line to the extremity, exclusive of the odd terminal plate. 
Four plates preceding the ultimate unite with the corresponding plates 
on the other side of the ray in the median radial line. A greater 
number of longitudinal series of abactinal plates in the radial areas 
are separated by papulae ; and small foraminate pedicellariae are 
occasionally present on the abactinal plates. In the armature of the 
adambulacral plates there are usually six spinelets in the furrow 
series, followed by five and six in the second and third series, the 
second series being subpapilliform. 
The actinal surface of the infero -marginal plates is covered with 
widely- spaced pits, upon which granules are borne. The widely- 
spaced granulation imparts a peculiar character to the ornamentation 
of these plates. The actinal intermediate plates are very large in 
relation to the size of the plates on the abactinal surface. In other 
respects this example accords with the description above given, ex- 
cepting the slight modifications dependent on larger size. 
Colour in alcohol, a bleached yellowish white, with a slight 
brownish shade. 
Locality.— L^i. 51° 1' K ; Long. 11°50' W. Depth 750 fathoms. 
Eemarhs. — This species is allied to Pentagonaster granularis, Eetz., 
sp., but is distinguished by the more pointed rays, by the union of the 
supero-marginal plates in the median radial line at the extremity of 
the ray, by the ornamentation of the marginal plates, by the character 
of the abactinal plates, and by the armature of tlie adambulacral 
plates. 
