80 T. GisLEX, 



proportion to the length of the arms. A distinguishing characteristic 

 of value might also be the distribution of the syzygies. In C. difici- 

 formis the syzygies are separated by 3 to -i. in G. manca by 9 to 10 

 oblique articulations. This difference is also to be found in the oii- 

 ginal descriptions, where the first-mentioned species is said to buve 

 syzygies with a syzygial interval of 2 — 0, the latter with an interval 

 of 4 — 10 (usually 7 — N) joints. The preceding species also seems to 

 be more slender and to have longer and narrower distal pinnules 

 than the one described below. 



It might be worth \\-iiik' to call attention to the fact that the 

 genus CnUomelra, as also many other Colohometrids, approaches in 

 many respects the Antedonid subfam. Perometrimv. Both groups have 

 an inconstant P;,. The Golobometrids^ being an Oligophreat family, have 

 unusually long pinnulars and eirrals, where the first-mentioned ones 

 especially are very similar to those of the Antedonidce. Perometrinw, 

 on the other hand, being a Macrophreat family, has short cin-als 

 and pinnulars. The basal rays are often absent in the Golobomdridtv 

 and the rosette very similar to that of the Macrophreats. Also the 

 centrodorsal cavity is unusually large. A feature distinguishing Go- 

 lobometrida' from Perometrime is the occurrence of a double spine-row 

 or a transverse crista on the proximal eirrals. On the distal segments, 

 however, the dorsal spine is single. If a reduction of the spines of 

 the proximals eirrals took place, we might probably refer a Golobo- 

 meirid to Perometrime. It seems therefore as if we should find con- 

 nections between Golobometridce and Peromeirince ; the latter is possibly 

 in this case to be deduced from the former .and has developed con- 

 vergently with the Antedonid typus (cf. p. 89 ff.j. 



Cyllometra manca (P. IT. Cakp.). 

 P^ig. ()0, 07. 

 Syn.: Anfeclon manca 1888 P. H. Carpenter Chall. Exp. Vol. 2<>. p 22(). 

 Cyllometra manca 1907 A. II. Clark Smiths Misc. Coll. Vol. 50, p. ;].J7: 

 1912 Crin. Ind. Oc, p. 156; 1913 Smiths. Misc. Coll. Vol. Gl: 15. p. :34; 1915 Mo- 

 nograph p. 89, 374; 1918 Si))oga Exp. Vol. 42 K. p. IIH. 



From St. 19: 1 specimen. 



i/ Sp. 1 Cd large, discoidal, fi-ee dorsal pole 2,8 mm. C. XXIII 23 

 — 25; 10—11 mm. in two whorls. All segments are shortei- than long. 



