A MONOGRAPH OF THE EXISTING CRINOIDS 493 



eight small segments. The following pinnules gradually increase in length and size, 

 and the segments of the later ones become more elongated ; but they never reach the 

 length of the large basal pinnules, nor are they very closely set. The disk is 10 mm. 

 in diameter, naked and deeply incised, almost to the center. Sacculi are not very 

 closely set on the pinnule ambulacra. The calyx and arm bases are white with darker 

 patches; the lower portions of the arms are a dirty brownish gray, and their outer 

 portions the same mottled with white. 



In the type specimen of Antedon brevicuneata, which I examined at the Leyden 

 Museum in 1910, the cirri are XXVIII, 20-23. The division series are not quite in 

 lateral contact; they resemble those of the type specimen of Antedon laevicirra but 

 are composed of slightly shorter segments. There are 39 arms. P 2 is large and stout, 

 tapering distally to a slender tip. The pinnules on the outer arms are considerably 

 larger than those on the inner. This specimen may be exactly matched with others 

 from the Philippine Islands that I have examined. 



Hartlaub in 1890 described Antedon amboinensis from some specimens from Ambo- 

 ina collected by Dr. J. Brock, as follows: The centrodorsal is flat discoidal, with the 

 cirri arranged in two marginal rows. The cirri are XXV, 20-25, from 14 to 17 mm. 

 long. The distal segments are sometimes carinate or bear a spine. The radials are 

 almost entirely concealed. The IBr : are entirely united laterally. The IBr 2 (axil- 

 laries) are short. IIIBr series are developed only on the outer side of the IIBr axil- 

 laries, so that there are 6 arms on each postradial series developed in 2, 1, 1, 2 order. 

 There are no IVBr series. The postradial series are in lateral contact. The arms are 

 not over 30, usually about 30, in number, and are 75 to 95 mm. long. The brachials 

 are short, triangular, and bluntly wedge-shaped. The second syzygy is from between 

 brachials 14 + 15 to between brachials 23+24, and the distal intersyzygial interval is 

 9 or 10 muscular articulations. The lower pinnules are moderately stiff but not re- 

 curved. They are of equal length on both sides of the arms. Pt is slender, especially 

 distally, a good deal shorter than P 2 , and composed of 16-20 elongated segments. 

 P 2 is markedly stiffer and thicker than P 1; 10-12 mm. long, with 12-20 segments, of 

 which the majority are longer than broad. PS is shorter and weaker than P 2 , but 

 longer than P!. The two following pinnules decrease hi length. The disk is 14-16 

 mm. in diameter and is strongly incised. Hartlaub said that this species recalls 

 brevicuneata but differs from that species in the entire lack of a lateral flattening of 

 the arm bases. 



In 1891 Hartlaub described'the five specimens from Amboina in greater detail: 

 The centrodorsal is thick and large, with a flat dorsal surface. The cirri are arranged 

 in two marginal rows. The cirri are about XXV, 20-25, from 14 to 17 mm. long. 

 The sixth and seventh segments are somewhat longer than broad, and those follow- 

 ing are about as long as broad, all of equal size. They become somewhat compressed 

 and may bear a dorsal keel or even a prominent spine. The radials are usually dorsally 

 visible at their sides. The IBn are short and broad, wholly or almost wholly later- 

 ally united. The IBr a (axillaries) are short, short pentagonal or almost triangular. 

 The IIBr and IIIBr series are 2. The IIIBr series are developed only on the outer 

 side of the IIBr axillaries so that there are six arms to each postradinl series. The 

 union of the axillaries with the preceding ossicles is generally not at all, or only slightly, 

 tubercular. The outer edge of the postradial series shows no thickening, but there 



