FISHERY BULLETIN: VOL. 70, NO. 2 



ones that have higher crowns and more rounded 

 bases (Figure 6i). 



After staining of the types of C. ecaudata, the 

 ventral shields in the thorax and abdomen are 

 darkest, except for a small area on the anterior 

 border of the first segment (cf. Figure 6e) . Most 

 parts of the collar, except for the anterior edge, 

 are stained in the types but may be whitish in 

 other specimens. Dark areas around the tho- 

 racic parapodia are separated from the shields 

 by a spottily stained longitudinal band. This is 

 especially obvious in specimens from British 

 Columbia. In some of the other Californian ani- 

 mals (AHF 003230), the thorax seems to stain 

 similarly laterally and ventrally under low pow- 

 er, but when viewed under 100 X, the lateral 

 areas appear in a granulated pattern, in contrast 

 to the uniformly stained ventral region. 



The dorsal pattern, beginning in the middle 

 thoracic segments (Figure 6j), is present in all 

 animals and seems to be very characteristic. 

 It results from the widening of the nonstaining 

 epidermis of the intrasegmental furrow. This 

 pattern continues on the anterior abdominal seti- 

 gers, but the unstained areas become progres- 

 sively narrower until, in the middle part of the 

 abdomen, the pale intrasegmental lines are as 

 narrow as the intersegmental rings. In some 

 Californian specimens (AHF, originally identi- 

 fied as C. yninuta) , a conspicuous subcircular spot 

 of heavily stained cells straddles each interseg- 

 mental furrow at the level of the parapodia in 

 the posterior thoracic and anterior abdominal 

 segments. The staining pattern was not studied 

 in the holotype of C. minuta. 



The variability of the ends of the radioles is 

 noteworthy; their shape is not related to size 

 or the region where collected. In material from 

 British Columbia (USNM 40303, 40304) , a com- 

 plete mature female, 11 mm long and 0.9 mm 

 wide, has six pairs of radioles connected for two- 

 thirds of their length by the palmate membrane. 

 The free ends of the radioles scarcely extend be- 

 yond the ends of the pinnules (Figure 6k) . Also 

 within the samples from California, the length 

 of the free ends of the lateral radioles is var- 

 iable, sometimes Vjeing intermediate between that 

 shown in Figures 6a and 6b, or is even shorter 

 (cf. Hartman, 1944b, Plate 24, Figure 59). The 



Cahfornian specimens (AHF), some of which 

 are mature, are up to 15 mm long, and have up 

 to 29 abdominal setigers and seven or eight pairs 

 of radioles (usually connected for half of their 

 length) . Although in other species of Chone the 

 width of the flanges (i.e., the extension of the 

 palmate membrane) varies between the dorsal- 

 and ventralmost radioles such that the ventral 

 ones appear slimmer, the relative length of the 

 free part is usually fairly consistent (see, how- 

 ever, C. infundibuliformis, p. 462). 



Retnarks: Chone minuta agrees with C. ecau- 

 data by its size, the shape of the collar, the fairly 

 distinct ventral shields, the form of the spatu- 

 late setae and anterior abdominal uncini, and the 

 dorsal staining pattern in the thorax (the last 

 character was not checked in the holotype of 

 C. minuta) . The variability in the length of the 

 free ends of the radioles of the specimens orig- 

 inally described as C. mimita is notable. 



Among the material identified by the Berke- 

 leys as C. gracilis, the lot from Horsewell Point 

 (USNM 40721) allowed staining; the pattern, 

 in addition to the form of the branchial crown, 

 the collar, the ventral shields, and the form of 

 the spatulate setae make identification certain. 

 The lot from Wreck Bay (USNM 40722) is re- 

 ferred here with some hesitation because of the 

 bad preservation. The branchial crown, ventral 

 shields, and the form of spatulate setae, how- 

 ever, agree with C. ecaudata. Berkeley and 

 Berkeley had recorded C. ecaudata from Wreck 

 Bay in 1950. 



With considerable hesitation, Japanese mate- 

 rial from Hokkaido, originally identified by Dr. 

 M. Imajima as C. teres, is included here. These 

 specimens correspond closely to the description 

 of C. teres by Okuda (1934), which, however, 

 does not refer to C. infundibulifor'mis (cf. p. 

 461). The collars are of even height ventrally 

 and laterally but are lowered dorsally, which is 

 not the case in typical C. ecaudata (cf. Okuda, 

 1934, Figure 3). The radioles end as shown in 

 Figures 6a and 6k. The uncini from anterior 

 segments differ considerably from those in pos- 

 terior segments ( Figures 61 and 6m) . The stain- 

 ing pattern dorsally in the thorax is similar to 

 that of C. ecaudata (Figure 6j) except that the 



476 



