A MONOGRAPH OF THE EXISTING CRINOIDS 549 



P., and P 4 ). These have wide basal segments, the later ones being longer and taper- 

 ing rather rapidly. The pinnules on the ninth and tenth brachials (P a and P 5 ) are a 

 good deal smaller than that on the eighth (P 4 ), but larger than the pinnules of the first 

 pair (P, and P.). The following pinnules gradually increase in length and slenderness, 

 their component segments becoming more and more cylindrical, but they never exceed 

 in length those of the third pair (P 3 and P c ). The terminal pinnules are again shorter, 

 and are very thin and delicate. The disk is lost. The diameter across the circle of 

 IIIBr axillaries is about 14 mm. Sacculi are numerous at the sides of the pinnule 

 ambulacra. The color in alcohol is brownish white, with the perisome darker. 



I examined this specimen at Leyden in 1910. The cirri are XXIV, 25. The 

 longest cirrus segments are about one-third again as long as broad. The ninth or 

 tenth and following segments bear small but prominent dorsal spines. There are 

 about 20 very long and slender arms. Six IIBr series and four IIIBr series, the latter 

 developed externally, are present. The synarthrial tubercles are slightly prominent, 

 and the basal portion of the arms is rugose as in Lamprometra palmata. The division 

 series are not in lateral contact, though they have tolerably straight sides. The IBrj 

 are entirely united laterally, but the axillaries are free. There are no lateral processes 

 such as are seen in Stephanometra. P 3 has 20-22 segments. P, is small and weak. 

 P 2 is nearly twice as long as P,, and P 3 is still longer. P 4 is nearly as large as P 3 , being 

 intermediate in size between P 2 and P 3 . P 6 is much shorter. The pinnules following 

 are small and weak. The proximal pinnules resemble those of the type specimen of 

 Alecto flagellata, but are slightly less stiffened and are more flexible and more flagellate 

 distally. 



Between this specimen and the type specimen of Alecto flagellata there appear to 

 be no differences not to be accounted for by the difference in the size of the two indi- 

 viduals, and there can be no doubt that in reality they represent the same species. 



The specimen collected by Dr. Brock at Amboina was thus described by Hart- 

 laub: The centrodorsal is a disk of medium size with a flat dorsal pole and entirely 

 marginal cirri. The cirri are fully XX, 22-27, about 15 mm. long. They are mod- 

 erately broad basally but more slender and more compressed distally. The sixth 

 and the three following segments are a little longer than broad. The 10 or 11 outer- 

 most segments bear small dorsal spines. The opposing spine is rather stout. The 

 radials are visible in the interradial angles of the calyx. The IBr] are short and broad 

 and are laterally united. The IBr 2 (axillaries) are short, broadly pentagonal or almost 

 triangular. The postradial series are not separated but are in lateral contact through 

 their outer edges. They divide not more than three times, and the IIIBr series, when 

 present, occur only on the outer side of the IIBr axillaries. All the division series 

 are 2 ; the axillaries are longer distally than proximally. The articulation between the 

 elements of the division series is faintly tubercular. 



There are about 25 moderately long slender arms 100 mm. in length, with a 

 smooth dorsal surface and composed of moderately short brachials. The first brachials 

 are rhombic and are almost completely united interiorly. The second brachials are 

 almost equally large but are markedly longer outwardly than inwardly. The first 

 syzygial pair (composed of brachials 3+4) is broader than long, and is followed by 

 five or six discoidal brachials. The surface of this portion of the arms is uneven in 

 that the articulation between the brachials is depressed on one side and raised on the 



