112 



BULLETIN 82, UNITED STATES NATIONAL MUSEUM. 



pair are suppressed, leaving the first syzygial pair, composed of the third and 

 fourth brachials, at the base of the arm. 



In a specimen of Nemaster iowensis (which I originally called Nemaster 

 irregularis) from Dominica the IIBr series are 4(3+4), and the IIIBr series 

 usually 1, rarely 2(1+2). 



In a magnificent specimen of Capillaster marice which I dredged in Kago- 

 shima Bay one of the IIBr series is 4(3+4), one is 2(1+2), four are 2 and three 



are 1 ; of the IIIBr series one is 

 4(3+4), three are 3(2+3), two 

 are 2(1+2), and one is 2; usually 

 the second and third brachials 

 form the first syzygial pair, but 

 sometimes the first and second. 



In a 28-armed specimen of 

 Capillaster multiradiata from 

 Ruck, Caroline Islands, recorded 

 by Hartlaub, two of the IIBr 

 series are 4(3+4) and eight are 

 2(1+2) ; the IIBr series of 

 2(1+2) are commonly followed 

 by IIIBr series of 3(2+3), with 

 one of 4(3+4) in which, as oc- 

 casionally happens, the first ossi- 

 cle has not been suppressed. 



A specimen of Capillaster 

 multiradiata from the Malay 

 Archipelago in 160 fathoms has 

 the details of the arm division as 

 follows : 



Ray 1 : Two IIBr series; that 

 to the left (viewed dorsally) bears 

 outwardly (on the left) a IIIBr 

 2 series and inwardly (to the 

 right) an undivided arm ; both of 

 the undivided arms arising from 

 the IIIBr series have the first 

 syzygy between the second and third brachials, but the (internal) undivided arm 

 arising from the IIBr series has the first syzygy between the third and fourth 

 brachials; the IIBr series to the right bears inwardly (toward the left) an un- 

 divided arm, in which the first syzygy is between the third and fourth brachials, 

 and outwardly (toward the right) a IIIBr 5(4+5) series, the two derivatives from 

 which have the first syzygy between the second and third brachials. The total 

 number of arms on this ray is six, arranged in 2, 1, 1, 2 order. 



Ray 2: Two IIBr 2 series; that to the left bears two undivided arms, in 

 which the first syzygy is between the third and fourth brachials ; that to the right 



FIG. 191. LATERAL VIEW OF TIPE SPECIMEN OF EDDIO- 

 CEINUS VENUSTULUS. 



