ANNOTATED LIST. 79 
Ophidiaster ophidianus. 
Asterias ophidiana Lamarck. 1816. Anim. s. Vert., 2, p. 567. 
Ophidiaster ophidianus Agassiz. 1835. Mem. Soc. Sci. Nat. Netichatel, 1, p. 191.—Ludwig. 1897. Seesterne 
des Mittelmeeres, p. 300; pl. 3, figs. 4, 5; pl. 8, figs. 18-30. 
Ludwig’s (I.c.) full account of this species is most satisfactory. It is the largest species 
of the genus, with R = 140-150 mm. or even more (as much as 265 mm. is recorded but this 
is perhaps an estimate) and has a brilliant coloration. The normal color is some shade of 
bright red or orange without spots or blotches. The geographical range is not extensive, 
including only the western Mediterranean and the Azores, Madeira, and Canary Islands. 
The bathymetrical range is small, for there is only one record and that a dubious one (near 
the Azores, 823 m., a very small individual in the Challenger collection) at a depth over 
105 m. The typical habitat is just below low-water mark and down to about 30 m. among 
and under stones and rocks. Greef (1882) records ophidianus from Sao Thomé and Rolas 
in the Gulf of Guinea, but as his specimens had the dorsal side variegated red or reddish- 
yellow with indistinct dusky bluish patches, it is more probable that they belong to the 
following species (guildingii). Unfortunately he says nothing as to their size. 
Ophidiaster guildingii. 
Gray. 1840. Ann. Mag. Nat. Hist., 6, p. 284. 
Although it has never yet been figured or even fully described, this is the common 
West Indian species of the genus and ranges from the Tortugas, Florida, to Tobago. It 
occurs on the under side of rocks and coral fragments near low-water mark. Verrill (1915) 
says that ‘‘a medium-sized specimen” has R =60 mm. andr=5mm. The largest specimen 
I have seen, among some 50 I have collected at the Tortugas, Jamaica, and Tobago, has 
R=56 mm. andr=7 mm. This proportion (R =8r) is typical of all the individuals I have 
found. Color in life is very variable. Young specimens (R =6 mm.) have no pigment, 
but by the time R =12 mm. they are considerably blotched with color. In mature speci- 
mens the ground-color ranges from pale yellowish through orange and scarlet to brownish- 
red, but this is more or less blotched with bluish, purple, maroon, or brown; some specimens 
show an almost uniform color, but this is unusual. Many specimens are almost identical 
in color with young Linckia guildingii, which occur in the same habitat. Mortensen found 
this Ophidiaster was breeding at Tobago in April 1916, and he succeeded in securing some 
early developmental stages. 
Undoubtedly O. guildingii is very nearly allied to O. ophidianus, but when specimens 
of the same size are compared side by side it is obvious that guildingii has more slender 
rays, coarser granulation, and larger and fewer papulx, besides the perfectly evident 
differences in the adambulacral armature, pointed out above. Apparently the West 
Indian species is much smaller than that of the Mediterranean, and its mottled coloration 
is also a distinguishing character. If the Ophidiaster which Greef (1882) found common 
at Sao Thomé and Rolas in the Gulf of Guinea proves to be this species, is will probably 
be found also at the Cape Verde Islands, a distribution corresponding to that of Linckia 
bouvieri, Eucidaris tribuloides, and several other echinoderms. 
Ophidiaster perrieri. 
De Loriol. 1885. Mem. Soc. Phys. Hist. Nat. Genéve, 29, No. 4, p. 17, pl. vii, figs. 3-37. 
This species is known only from Mauritius, whence Robillard sent de Loriol a single 
specimen. The description and figure given are entirely satisfactory, as 1s so generally 
true of de Loriol’s careful work. The species is notable for the isolated papule on the 
actinal surface, the presence of which indicates a trend towards Hacelia. 
