196 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.42. 



Though indicating the connection between the genus Plirynocrinus 

 and the genera Rliizocrinus and Bathycrinus, this new genus is evi- 

 dently much closer to the former than to the two latter, and should 

 be placed \nth it in the same family. 



This is the first stalked crinoid to be described from the Hawaiian 

 Islands; and it is interesting to note that it is so closely related to a 

 Japanese form {Plirynocrinus), and, moreover, that it possesses a 

 lesser degree of specialization that the latter;^ for from the evidence 

 at hand it appears that the crinoid fauna of southern Japan v,as 

 derived largely from that of the South Sea Island region by way of 

 the Hawaiian Islands, and not from the lands lying directly to the 

 southward. 



NAUMACHOCRINUS, new genus.^ 



Genotype. — Naumachocrinus Jiawaiiensis, new species. 



Diagnosis. — Stalk attached distally to a terminal stem plate as in 

 Plirynocrinus, entirely wdthout radicular cirri; distal third of stem 

 robust, the columnars resembhng those of Plirynocrinus, but shghtly 

 longer; proximal two-tliirds of stem much more slender, resembling 

 that of the larger species of Rhizocrinus, such as R. weheri. 



Calyx cylindrical, greatly elongated, twice as long as broad, 

 resembling in general appearance that of Rhizocrinus rawsonii or 

 R. weheri; but the basals are exceedingly short, low triangular, over 

 three times as broad as long, just in apposition at their lateral angles, 

 and the radials are enormously elongated, about three times as long 

 as their distal breadth, the relation between these two circlets of 

 plates being just the reverse of that characteristic of Rliizocrinus. 



NAUMACHOCRINUS HAWAHENSIS, new species. 



Stem. — The stem is 237 mm. long, and is composed of 60 columnars, 

 the distalmost attached to the remains of a heavy terminal stem 

 plate resembling that of Plirynocrinus; the distal 75 mm. of the stem 

 is composed of 12 massive columnars of the type characteristic of 

 Plirynocrinus, but proportionately longer. The distalmost columnar 

 is 6.5 mm. across the expanded ends, which are very narrowly oval, 

 the long axes being at right angles to each other, and 6.5 mm. long; 

 about its center runs a more or less irregular broad raised band; the 

 following columnars are similar, very slowly decreasing in size, the 

 tenth (from the terminal stem plate) being 4.5 mm. across the very 

 narrowly oval ends and 6 mm. long, and the eleventh 4.5 mm. across 

 the distal and 4 mm. across the proximal end, and 5.5 mm. long; the 

 twelfth is 4 mm. across the distal and 3 mm. across the proximal 

 end, and 4.5 mm. long; the proximal end is very broadly oval, but 

 the distal end is narrowly oval like the proximal end of the eleventh 



1 See Proc. U. S. Nat. Mus., vol. 38, pp. 115-118, and pp. 211-216. 



' From vavfiaxK (vavc+tiixeuai), a marine or sea fighter, + Kpivtv, a lily. 



