The CRixoins from Dr. S. Bock's Expedition to Japan l!U4. i;{3 



(18—20) pinnulars on Pj — P^, (P., > Pj > P,). atul usually has somewhat 

 fewer cin-als. An examination of more ample material will pi-obably 

 show that the two forms belong to the same species. 



A. H. Clark 1!>1<S in the Siboga work gives Antcdon 'iniiiata as 

 a synonymous form of /. ((dresline. If this is correct there might 

 be a mistake in the clesci'iption ol' fli<' tirsl-nicntioneil species. /. lulrestine 

 is said to have P, H>; U> nun. and in (his case .1. iimiiitd. can scarcely 

 ha\"e Pj IS; ;{ nun. because (d' a I'ulc lliai one always liiuls verified 

 in the examination of growth-series of Crinoids and that i-uns thus: 

 Length and number of segments of a cirrus, an ai-m or a pinnule 

 stand in a certain rclaiion (o the (inlogeiiclical de\cltipuicnt and in a 

 cerlain I'elative proportion, viz. that younger s|)eciinens \\i\\v sliuilcr 

 ciiii, arms, and pinnules and fewer cirrals and pinnulars, than the lull- 

 grown ones. The figures obtained by these characteristics are rather 

 constant in relation to one another at a given size and when compared 

 with the same charactei'istic in (tidcr and younger individuals of the 

 same species they can be titted into an arithmetical series. 



Dorometra A. H. Clakk. 

 D. nana (H.\rtl.\ub|. 



Fig. 123, 124. 

 Syn.: See 1918 A. II. C'lakk Siboga Exp. Vol. 42 B, p. 21(5. 

 From St. 41: 3 specimens. 



Sp. I (St. 41) The free, flat, dorsal pole of Cd about O.r, nun. ('. 

 LI 10—14; 4—8 mm. 1^' segment short, 2'^ cubical, 3^' L= l';2 — 2 X 

 br, 4'''' — T^ segment: L = 2 — 3 X br, then shorter again. Antepenul- 

 timate cii'ral L = l'/2 br, penultimate segment L = I'/s br, with a pointed 

 opposing spine, h = '2 of the br of the segment. Terminal claw cur- 

 ved, somewhat longer than the preceding segment. 



r Br 1 almost concealed by Cd. Axillaiy rhombic, ii = -3 br 

 with a slight synarthrial tnbei'cle in the proximal part. Arms X, 30 — 

 35 mm. Br — s I basally united inside. Br 2 with a small, backward 

 directed synarthrial tubercle; this ossicle is narrower than Br I, by 

 which a broad interspace (= '2 of the; iir of the arm) arises between 

 the arin-l)ases. Syzygies:. 3 + 4, !) -|- 10, 14+ !"> etc. with an intcr\"a! 



