A MONOGRAPH OF THE EXISTING CRINOIDS 33 



the division series there are relatively long, straight, pointed, and scattered spines 

 which are especially numerous along the edges. Occasionally (as in two specimens 

 from Montserrat) these are entirely confined to the ambulacral margins of the ossicles. 

 There are 30 arms about 100 mm. long which even at the base, and especially farther 

 out, are strongly compressed laterally. The first brachials are somewhat broader than 

 long and are not entirely in contact interiorly. The second brachials are squarish. The 

 first and most of the second brachials bear spines resembling those of the elements oi 

 the division series on their proximal and distal edges. The first syzygial pan (composed 

 of brachials 3+4) is as long as the first and second brachials together. The epizygal 

 (fourth brachial) has several stronger spines on its distal border of which one is especially 

 strong. The five following brachials are approximately as long as broad, and those 

 succeeding are trapezoidal, gradually passing to approximately triangmar. The bra- 

 chals remain triangular until about the middle of the arm when they again become 

 trapezoidal. The brachials in the proximal third of the arm are rather strongly saddle- 

 shaped The five or six brachials following the first syzygial pair have on each side 

 of the distal edge a small group of minute spines, and a single spine on the dorsal surface 

 It also stands near the" distal edge. These sharp dorsal spines, wl-h-e directed 

 obliquely distally and outwardly, have at first a more central position, but they soon 

 m v'e othe longer side of the brachials so that they come to alternate in position on 

 succeeding brachials. The stoutness of the dorsal spines is already considerable on the 

 Tenth Trachial, and increases rapidly and markedly at ^™ ^^^ 

 comes like that of a curved pick, strongly compressed laterally. The baa .of the si nes 

 becomes constantly longer and finally extends for the entire length of the dorsal surfac 

 of the brachials. In the outer half of the arms the stoutness of the spines decreases 

 „o-nin corresponding to the decrease in size of the brachials 

 g The ^"t syzy g ; is between brachials 3 + 4 and the second from between brachials 

 34+35 to beuLn brachials 39+40, or even farther out-between brachials 45+46 

 fc ItsLcLol Lm Montserrat. Then there is usually an interval of 7 "*»**««* 

 aTn's aTd the distal intersyzygial interval is 4-6 muscular *****"££ £«£ 

 from Blake station 298 (Barbados) has the second syzygy frequently between biacluals 

 91 4-10 and in one arm it is between brachials 15+16. 



21+ p7oT In outer arm from a IIBr axillary is weak and f^^f^f^^ 

 length sometimes about 12 mm. long with about 20 segments. P, u .13 n m J on | . * » 

 lengin, iwuiu slender P 4 is scarcely half as long, with 9-1U 



f-tl ThTs™ ts of aS LT^Z ! are ro'nnded .nig,,,,,!,- along, ted with 

 ^ex ». Jn of T ou ermost and L basal which, however, are somewhat longe 



S2S.S^ £. toSl/BoUt these *£$£%£* 

 on the pionoles following and peraist far wW"™**?"^^ J e ir Z broad- 



843803—50 i 



