BANSE: REDESCRIPTIONS OF SOME SPECIES OF CHONE AND EUCHONE 



30//: a, 45//:h,k; 90/<: c,i,j 



Figure 2. — Chone duneri, from Point Barrow : a, middle uncinus from fourth abdominal 

 setiger; b, ventral view of anterior end of thorax after staining; C. auranfiaca; c from 

 holotype, others from USNM 43637: c, uncinus from second abdominal setiger; d, an- 

 terior end from the right side ; e, end of median radiole, somewhat schematic ; f , g, an- 

 terior end in dorsal and ventral views after staining. Slightly schematic, branchial 

 crown omitted; h, i, bayonet and spatulate setae from sixth setiger; j, uncinus from 

 fourth setiger; k, uncinus from approximately 60th (12th to last) abdominal setiger. 



racic setiger; Ushakov (1955) has specifically 

 stated that it is absent. This character was one 

 of the main reasons for describing C. bimaculata; 

 at that time it was not realized that all Chone 

 species have such a ring. Contrary to the orig- 

 inal description, the intersegmental furrows of 

 the paratype do not stain and the thoracic intra- 

 segmental furrows, in the plane of the parapodia, 

 are ventrally interrupted by the strongly stained 

 longitudinal midventral line (cf. Banse and Nich- 

 ols, 1968, Figure 2j ) . Thus, there is no justifica- 

 tion for maintaining C. bimaculata. 



The record of C. duneri from Labrador (Petti- 

 bone, 1956, USNM 23635, 2 specimens) is a 

 Euchone sp. with conspicuous ventral shields. 



CHONE AURANTIACA (JOHNSON) 



Figure 2c-k 



MEG AC HONE AURANTIACA Johnson, 1901, 

 p. 430.- Hartman, 1938, p. 19; 1959, p. 549. 



Diagnosis: A large Chone species without 

 ventral shields. Branchal basis shorter than the 

 slightly oblique collar. About 25 pairs of radioles 

 connected for four-fifths of length by palmate 

 membrane, with free ends short and tapered. 

 First bundle of setae small, inserted at same 

 level as following notosetae. Spatulate setae 

 without pointed tips. Abdominal uncini uni- 

 form, with a few columns of three to four coarse 



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