184 THE RECENT CRINOIDS 
are externally developed. The lateral tubercles on the rays 
are well developed and thick. P, is the largest, with sixteen 
or seventeen segments; P, is similar, but not quite so 
long; P, is much shorter than P,, but stiff, with eleven 
or twelve segments; P, is slightly shorter than P, and is 
like the succeeding pinnules instead of stiff like the pre- 
ceding, though it may be a trifle stiffer than its successors. 
Dichrometra flagellata (J. Miiller). 
Alecto flagellata 1841. J. Mitisr, Archiv für Naturge- 
schichte, 1841, J, p. 145. 
Alecto elongata 1841. J. Mörrer, idem, p. 146. 
Dichrometra flagellata 1909. A. H. Crarx, Proc. Biol. Soc. 
Washington, vol. 22, p. 13. 
No locality (coll. Brugmans). — The centrodorsal 
is rather large, with the dorsal pole concave; the cirrus- 
spines are very small and tubercular; the cirri are XL, 
24, 25, 28 and 30. There are thirty-nine arms, the extra 
(IIIBr) division series being developed externally. The di- 
vision series and first six or eight brachials are in close 
apposition, and are sharply flattened laterally. P, is very 
small and short; P, is large, over twice as long as P,, 
of the same character as the same pinnule in D. protectus; 
the component segments are slightly longer than broad; 
P, is slightly longer and larger than P,; P, is about the 
size of P,; P, is somewhat smaller than P,; the following 
pinnules are small and weak. The enlarged lower pinnules 
are strongly curved outward and backward; they stand 
out very prominently through their large size, the middle 
and outer pinnules being especially short. 
New Guinea (coll. Salomon Müller) (type of 
Alecto elongata). — The cirri are XXIV, 25; the longest 
cirrus-segments are about one third longer than broad; 
the ninth or tenth and following bear small but prominent 
dorsal spines. There are about twenty very long and slender 
arms: six IIBr series and four IIIBr series (developed 
Notes from the Leyden Museum, Vol. X XXIII. 
