The Crinoids from Dr. S. Bock's Expedition to Japan 1914. 121 



Br 1. Anns X, 70 mm. Br 1 and 2 with a carination similar to the 

 one on the I Brachials but very much slighter. Br-s 1 inside conti- 

 guous in pairs, outside broader, as also Br 2. Syzygies; 3 + 4, 13 + 14, 

 18+19... distally with an interval of about 5 oblique articulations. 

 Br 1 — 10 (iiscoidal, then irregularly oblique joints. The proximal ossicles 

 rounded and smooth; from Br 15 a low, median, longitudinal crista, 

 slightly projecting in lateral profile. 



P^ 13; 5 mm. P., 13; 5 mm. P2 8—9, 3,5 mm. P3 similar. P^ 

 coarser than P2. The segments rather uniform, smooth, a little longer 

 than broad, distally somewhat angular. P4— P12 ih 10; 3 — 4 mm. (Proxi- 

 mal segments very slightly dorso-ventrally flattened). Distal p-s + 14; 

 5 — (3 mm. (P* and 2'' segments shorter and a little coarser than the 

 following ones, which have the L = 2 br). 



Disk a little incised, with large calcareous granules, diameter 

 4 mm., colour brown. Otherwise the animal is light yellow-brown. 



This new species resembles most closely P. lata from which, 

 however, it differs sharply by the cirri, very short in comparison with the 

 arm-length but in spite of this with relatively many segments, by 

 the rather smooth proximal arm-parts, and, above all, by the proximal 

 pinnules, which have a few, rather long pinnulars. 



After a comparison with specimens of Dr Mortensen's collection 

 I am convinced that this species often has XI or XII arms attaining 

 a length of > 70 mm. II Br-s are 2. Pj might get 15 segments and 

 attain a length of + mm. P.2 — P^o «'"e short, w'xih. the 5 — first seg- 

 ments somewhat thickened in dorsal view. 



In the short genital pinnules has the species an unusual resem- 

 blance to a spider, whence the name. 



Diodontometra n. gen. 



This exeedingly peculiar type of the family Charitometridce re- 

 sembles the genus Gharitomeira by the strongly expanded proximal 

 segments on the genital pinnules. Prom this genus it differs, however, 

 in several characteristics. The arms are XX, the II Br-s: 2. Cd is 

 high and pointedly conical and the cirri arranged in radial groups, 

 separated by large interradial interspaces. And, finally, the opposing 

 spine is divided into two prominences standing side by side and usu- 



Nova Acta Reg. Soc. Sc. Ups., Ser. -4, Vol. n. N:o 6. Impr. -"h 1922. . 16 



