io6 ^ 
to a smaller blunt proximal tubercle; the spines change but little distally, their bases becoming 
slightly shorter and their apices consequently sharper, and the hypothenuse straight; the opposing 
spine is longer than the spines on the preceding segments and more slender, median or sub- 
median, nearly or quite erect, nearly or quite equal to the diameter of the penultimate segment 
in height; the terminal claw is longer than the penultimate segment, very long and slender, 
slightly and evenly curved ; the longer earlier segments have slightly enlarged ends ; this 
becomes less in the spiniferous distal segments, though it is traceable quite to the penultimate. 
The division series and arms resemble those of D. fiagellata, but are much more slender 
and delicate; the division series and first brachials may be well separated, or they may be in 
lateral contact; they are usually not quite in apposition, though they have straight lateral edges 
which are usually slightly swollen ; the characteristic rugose appearance of D. fiagellata, due 
to the low, though prominent synarthrial and articular tubercles is reflected in a delicate and 
modified form. 
The arms are i6 — 23, 70 mm. to 80 mm. long. 
Pj is from 6.0 mm. to 6.5 mm. long with 15 — 18 segments of which the first is short, 
the second nearly as long as broad, the third about as long as broad, and the seventh or 
eighth and following slightly longer than broad. Pj is 7 mm. long with 22 segments of which 
the first is short, the second about as long as broad, the third slightly longer than broad, the 
seventh or eighth and following half again as long as broad, becoming twice as long as broad 
terminally; the pinnule is very slightly stouter basally than Pj, but tapers less rapidly and more 
gradually, and is less flagellate distally. P., is 9 mm. long with 23 segments, resembling P„ but 
proportionately stouter. Pj is 8 mm. long with 20 segments, resembling P.^; the second-fourth 
segments are sometimes very slightly enlarged. P^ is 4.5 mm. long with 14 segments, of the 
same character as P^ but proportionately smaller. P^ is 4.2 mm. long with 13 segments, similar 
to P3. Pj is 3.7 mm. long with 12 segments, similar to Pg. The following. pinnules are of about 
the same length and stoutness, becoming weaker and more delicate distally. The distal pinnules 
are 6 mm. long, very slender, with 18 — 19 segments. 
In nearly every detail of its structure this species agrees with D. fiagellata \ with the 
specimen of the latter which served Muller as the type of his A lee to elongata the agreement 
is especially close, in the number of cirri, the number of cirrus segments, the number of the 
cirrus segment which bears the first dorsal spine, the proportions of the lower pinnules, and 
the number of their component segments. But the great slenderness of the cirri, which have 
greatly elongated distal segments serve easily to distinguish it. 
2. Dichrometra fiagellata (J. Muller). 
, J. Muller. Archiv fiir Naturgesch., 1841, I, p. 145. [Alecto fiagellata); p. 146 [Alecto elongata). 
Hartlaub. Nova Acta der Ksl. Leop. -Carol, deutschen Akad. der Naturforsch., vol. 58, 1891, 
N" I, p. 71, pi. 4, fig. 47 [Antedon elongata); p. 73, pi. 4, fig. 45 {Antedon fiagellata). 
A. H. Clark. Vidensk. Medd. fra den naturhist. Forening i Kobenhavn, 1909, p. 172. 
Notes from the Leyden Museum, vol. 33, 191 1, p. 184. 
Crinoids of the Indian Ocean, 1912, p. 150. 
