226 Clark — New Genera and Species of Crinoids. 



Cirri xxx, 21-28 (usually about 25), 10mm.-12mm. long; first six or 

 eight joints not so long as broad, the remainder squarish; dorsal surface 

 of the joints smooth, rarely in the terminal two or three with a slight 

 trace of a minute central tubercle; opposing spine prominent, though 

 small, reaching to not more than about one-third the diameter of the 

 penultimate joint in length; terminal claw rather longer than the penul- 

 timate joint, moderately curved. 



Radial* concealed by the centro-dorsal ; first costals slightly trapezoidal, 

 very short, four times, or rather more, as broad as long; costal axillaiies 

 about half again as broad as long, and, like the first costals, free laterally; 

 seven distichal series are present, one of 2, the remainder of 4 joints 

 with a synarthry between the first and second and third and fourth;* the 

 second distichal, except when axillary, always bears a pinnule; there are 

 three palmar series of 2, of which the second is not an axillary, these 

 being, therefore, strictly homologous with the distichal series in Uinta- 

 crinus, and in the abnormal specimen of Heliometra tanneri which I 

 described not long ago.t Seventeen arms about 55mm. long, resembling 

 those of C. manca or C. albopurpurea; the pinnule of the fourth (epizy- 

 gal) brachial is present on about half of the arms. 



Color (in spirits). — White, the cirri with narrow bands of light purple, 

 the polar area of the centro-dorsal deep purple, the division series and 

 discoidal lower brachials with a median line of purple, the remainder of 

 the arms crossed by purple hands about equal to one brachial in width, 

 separated by white bands of the same width. 



Type locality. — nil' Nipon, Japan. 



Type, in the collection of the University of Copenhagen, 



Geni - OLIGOMETRA A. II. (lark. 



Oligometra pulchella sp. nov. 



This is a delicate and rather slender species, similar in general build to 

 0. gracilirirra from the Philippine Islands, though the cirri are propor- 

 tionately only one-half as long, with about half as many joints. 



Centro-dorsal discoidal, the large polar area circular, Hat, and unmarked ; 

 cirrus sockets in a single marginal row. 



Cirri xiv, 16-23 (usually about 18), 7mm. long, comparatively slender; 

 first joint short, the following gradually increasing in length to the sixth, 

 which, with those following, issquarish; fourth and following joints with 

 a low transverse ridge extending entirely across the flattened dorsal sur- 

 face of the joints, in the earlier joints suhterminal in position, at about 

 the eighth becoming median; this ridge is finely spinous, and appears as 

 a very small dorsal spine in lateral view; opposing spine delicate, median 



* This is an entirely new type of a rm Structure ; in all other eases where the distichals 

 are four in Dumber, the two outer are united bysyzygy. I have already pointed out, 

 however (Proc. (J. 8. Nat. Mus., XXXV, p. 127, 1908), that this syzygy was in reality 

 occupying the position of a synarthry, though I « l i < I not then know of any species with 

 this more primitive t.\ pe of arm-structure. 



t Proc. U. S. Nat. Mus., XXXIV, p. 267, tig. I. 



