THE STARFISHES OF THE HAWAIIAN ISLANDS. 
1107 
I' rays being there pressed together. Disk not elevated above actinal surface of arms, from which it is 
marked off by a slight constriction. 
The abactinal plates are not very regular as to shape, but may be said to be cruciform with short 
rounded processes, by the tips of which adjacent plates imbricate. The median radial series is most 
regular, and can be easily distinguished. The other abactinal plates are often rather irregular, and 
small intermediate ossicles may be interpolated to complete the close mesh work, which forms roundish 
or irregular papular areas, rather smaller than the plates, and containing each 1 or 2 papulae. The 
plates themselves are convex and each bears 1 (less commonly 2 or 3) short, stout, subclavate, bluntly 
pointed spinelet. The spinulation of the disk and rays is the same. In addition, each plate bears 
1-3 spaced, small, broad-tipped, crossed pedicellarise (see pi. xli, fig. 3b) . The jaws when viewed 
[ from the broad side are quite spatulate, and broader than is usual in this type of pedicellarise. 
Sometimes the pedicellarise appear to be attached to the membrane of the papular area. 
Immediately external to the adambulacral plates is a series of much larger, convex, subcordiform 
plates, possibly representing the inferomarginals. Each of these bears, in a transverse slightly oblique 
series, 2 blunt, robust, tapering, often slightly curved spines, much larger than any of the abactinal or 
lateral spinelets, and rather more robust, though not longer, than the adambulacral spines. Occasion- 
ally only one spine is present. At the base of the ray a few plates have an accompanying forficiform 
pedicellaria, 4 or 5 times as large as the ordinary forficiform variety, and with rounded denticulate 
tips to the jaws. The superomarginal plates are strongly cruciform, the longest axis being transverse 
and somewhat oblique. In addition to the usual spaced pedicellarise each plate bears a single spinelet, 
identical in shape, but sometimes a trifle larger than those of the abactinal plates. The whole test is 
overlaid with a thin skin which invests plates, spines, and pedicellarise. The spinelets are quite easily 
broken off. In alcoholic specimens they are movable. In general both spines and pedicellarise appear 
numerous. 
The adambulacral plates are small, short, and band-like, and each bears a cylindrical, untapered, 
often subclavate, blunt spinelet. Relatively few of the plates have 2 subequal spinelets, but 1 is the 
rule. Usually the spinelets are a trifle curved, and some have a curious elbow at the base. Like the 
rest of the test the adambulacral plates and spinelets are invested with thin membrane. Each mouth 
plate has a large forficiform pedicellaria on the actinostomal border adjacent to the enlarged, clavate, 
pointed mouth spine. Actinostome small, closed by the two mouth spines of each angle. 
Madreporic body small, convex, situated nearer margin than center. Striations are in the form 
of curved or irregular slits, not continuous lines. Along adcentral border of the body are 6 or 7 spines, 
belonging to the adjacent (basal?) plate. 
Locality: Station 3867, Pailolo Channel, between Molokai and Maui islands, 284 to 290 fathoms, 
fine sand and mud; bottom temperature, 44° ; 1 specimen, type no. 21189, U. S. National Museum. 
This is a very distinct, and in one respect, aberrant species of Hy dr aster ias. Both H. ophidion and 
H. richardi are diplacanthid, but H. verrilli usually has only 1 spine to each adambulacral plate. In 
general form the present species resembles ophidion more than richardi (which is probably immature). 
Verrilli differs from ophidion in the following respects: Verrilli has usually but 1 terete, untapered, 
adambulacral spine, ophidion 2, tapered; verrilli has no small forficiform pedicellarise on the furrow 
margin, ophidion has; verrilli has 2 relatively large inferomarginal spines, ophidion 1 small one; verrilli 
has a number of large proximal inferomarginal forficiform pedicellarise, together with 1 large one on 
each mouth plate, ophidion lacks these. Other differences exist in the form of the abactinal plates, 
spines, and pedicellarise, as well as in the relative size of the spines of the disk and rays. ' The 
madreporic bodies also are different. Verrilli is not especially closely related to richardi, from which 
it differs considerably in general form and in details of armature. 
This species is named for Prof. A. E. Verrill, of Yale University. 
Family BR1SINGID7E G. 0. Sars, 1875 . 
Brisingidae, G. 0. Sars, On some Remarkable Forms of Animal Life from the Great Deeps off the Norwegian Coast, 
II. — Researches on the Structure and Affinity of the Genus Brisinga, 1875, p. 101. 
Key to Hawaiian genera of Brisingidse. 
a. Abactinal membrane of disk and basal portion of arms punctured by conspicuous papulse. . .Omnia 
aa. No papulge present Bkisinga 
