ANNOTATED LIST. 125 
alexandri has more numerous arm-spines than pumila, much longer arms than valenci@, as 
highly specialized a disk-covering as either, and in addition a well-fixed color-mark on the 
oral surface, it seems fair to consider it the most highly specialized member of the genus. 
In regard to the type species of Ophiocoma, there is room for disagreement. In 1865, 
Lyman definitely designated ‘‘O. scolopendrina Agass.” as the type. But there is no such 
species anywhere in literature as “‘O. scolopendrina Agass.,” and therefore, in 1915, I 
named “‘Ophiura echinata Lamarck 1816” as genotype, saying: ‘“‘Type determined by the 
fact that Agassiz mentions but two species and echinata alone is identifiable.’’ A careful 
examination of Agassiz’s statement when instituting the genus shows that he gives as the 
constituent species ‘‘O. squamata Ag. (Ophiura squam. Lam.)—0O. echinata Ag. (Ophiura 
echin. Lam.) ete.’’ Since squamata is not certainly identifiable, it would seem that echinata 
is obviously the type of the genus but clearly Lyman interpreted the ‘‘ete.’’ of Agassiz’s 
statement to include all the rest of Lamarck’s species of Ophiura to which the diagnosis 
of Ophiocoma as given by Agassiz applied, and he accordingly, for some reason best known 
to himself, selected scolopendrina. As there is no obvious reason why he should not have 
done so, his designation stands and my later choice of echinata seems to be superfluous. 
Fortunately, scolopendrina and echinata are so very closely allied that it is only with great 
care that they can be distinguished. Many specimens would be almost indistinguishable 
were the locality whence they came not known. It is therefore of no importance which is 
regarded as the genotype. 
Ophiocoma echinata. 
Ophiura echinata Lamarck. 1816. Anim. s. Vert., 2, p. 543. 
Ophiura crassispina Say. 1825. Jour. Acad. Nat. Sci. Phila., 5, p. 147. 
Ophiocoma echinata Agassiz. 1835. Mém. Soc. Sci. Nat. Netichatel, 1, p. 192. 
Ophiocoma serpentarig Miller and Troschel. 1842. Sys. Ast., p. 98. 
Ophiocoma dentata Miller and Troschel. 1842. Sys. Ast., p. 99. 
Ophiocoma tumida Miiller and Troschel. 1842. Sys. Ast., p. 100. 
Ophiocoma crassispina Liitken. 1859. Add. ad Hist. Oph., pt. 2, p. 142, pl. iv, figs. 7a-7d. 
This is one of the commonest brittle-stars of the West Indies, occurring from Bermuda 
to “Aspinwall ”’ (Colon) and Brazil, in shallow water, wherever conditions are at all suitable 
for any echinoderms. A specimen in the Paris Museum is said to be from Liberia, and it is 
quite possible that the species occurs on both sides of the Atlantic. It reaches a large size, 
& specimen in the Museum of Comparative Zoédlogy measuring 30 mm. across the disk. 
The color is ordinarily more or less uniformly black, but it is very common to find speci- 
mens with the disk variegated with white or even wholly whitish. The arms, particularly 
near the tips and in young specimens, are apt to be banded with light and dark shades. 
The oral shields are unusually constant in shape in this species, and are quite characteristic; 
they are usually longer than wide, but even if wider than long, the inner end is as wide as 
the outer. The uppermost arm-spines are often short and thick or even swollen, but they 
are not claviform, and not rarely they are quite slender. While easily distinguished from 
the other West Indian and the Panamic Ophiocomas, echinata is surprisingly near the com- 
mon Indo-Pacific scolopendrina, from which it can only be certainly distinguished by the 
comparison of all the characters. 
Ophiocoma scolopendrina. 
Ophiura scolopendrina Lamarck. 1816. Anim. s. Vert., 2, p. 544. 
Ophiocoma scolopendrina Miiller and Troschel. 1842. Sys. Ast., p. 101.—H. L. Clark. 1915. Mem. M.C. Z., 
25, p. 298, pl. 14, figs. 10, 11. 
? Ophiocoma variabilis Grube. 1857. Arch. f. Naturg., Jhrg. 23, 7, p. 342. 
Ophiocoma molaris Lyman. 1861. Proc. Boston Soc. Nat. Hist., 8, p. 79. 
Ophiocoma alternans von Martens. 1870. Arch. f. Naturg., Jhrg. 36, 7, p. 251. 
Ophiocoma lubrica Koehler. 1898. Bull. Sci., 37, p. 76, pl. iii, figs. 23, 24. 
(Plate 13, Figure 9.) 
This very common and widely distributed Ophiocoma ranges from the Cape of Good 
Hope and the Arabian Gulf on the west to Hawaii and the Paumotu Islands on the east. 
