BANSE: REDESCRIPTIONS OF SOME SPECIES OF CHONE AND EUCHONE 



1934. Originally identified as C. minuta. AHF 

 003230, 5 specimens of a larger sample. 



Holotype of C. minuta from Dillon Beach, 

 Calif., in holdfasts of algae and among compound 

 ascidians, 14 June 1941. AHF n 417; type AHF- 

 67, Poly. 0182. 



Wreck Bay, British Columbia, 1921 (see Berk- 

 eley and Berkeley, 1932, as C. gracilis) . USNM 

 40722, 16 specimens. 



Wreck Bay, west coast of Vancouver Island, 

 1925. Collected and identified by E. and C. 

 Berkeley (see Berkeley and Berkeley, 1950). 

 USNM 40303, 2 specimens. 



Horsewell Point, British Columbia, in sea- 

 weed, 25 Apr. 1934. Collected by E. and C. 

 Berkeley and identified as C. gracilis. USNM 

 40721, 2 specimens. Unpublished record. 



Dodd's Narrows, British Columbia, 19 June 

 1957. Collected and identified by E. and C. 

 Berkeley. USNM 40304, 1 specimen. Unpub- 

 lished record. 



Pavlov Bay, Alaska (see Berkeley and Berke- 

 ley, 1942, as C. gracilis) . USNM 40723, 3 spec- 

 imens. 



Samami, Hokkaido, Japan, Aug. 1970. Col- 

 lected by M. Imajima and identified as C. teres. 

 USNM 45267, 3 specimens out of a much larger 

 original sample. 



Additions to the Description: The syn types 

 of C. ecaudata are mature females. The com- 

 plete holotype has 18 abdominal setigers and is 

 about 9 mm long (total) ; the paratype is a larger 

 anterior fragment which is almost twice as wide. 



A palmate membrane that "extends well over 

 half the length of the radioles" (cf. Hartman, 

 1942a, p. 136) connects seven pairs of radioles 

 bearing pinnules. A few pairs of nude filaments 

 are present ventrally, the longest being almost 

 half as long as the radioles proper. The ends 

 of the radioles beyond the origin of the distal 

 pinules are rather short dorsally (cf. Figure 6a) . 

 Laterally and ventrally, the ends can be "coiled 

 like a watch spring" (cf. Moore, 1923, p. 246), 

 having long filiform tips and being about a quar- 

 ter as long as the entire radioles. A ventral 

 radiole may be present, as long as the others but 

 with an especially long terminal portion, the pin- 

 nules not extending as far as on the other radioles 



(Figure 6b; in one of the types, and USNM 

 40304). 



The low collar barely conceals the bases of the 

 branchial crown. When closed, it overlaps dor- 

 sally (Figure 6c) ; when open as in the holotype, 

 it is formed as shown in Figure 6d (from another 

 specimen; the outer heavy lines in this figure 

 correspond to the edges of the collar in Figure 

 6c; the anterior incision extends almost to the 

 level of the first bundle of setae in the holotype 

 of C. minuta) . 



Ventral shields and intrasegmental furrows 

 are more or less visible depending on the con- 

 traction of the animals (Figure 6e). After weak 

 staining, however, the ventral shields and the bi- 

 annulated character of the setigers are very dis- 

 tinct as far as the middle of the abdomen in all 

 animals. 



The first (buccal) segment (Figure 6e) is un- 

 usually large and distinct ventrally. The anteri- 

 or border of the first setiger approaches the pos- 

 terior border dorsad to the setae (Figures 6c 

 and 6d) . This bundle of setae is as large as those 

 of the following notopodia and emerges on the 

 same level. Rounded anterior and posterior no- 

 topodial lips are conspicuous. The limbate setae 

 originate above the lips. All specimens have 

 spatulate setae with long tips (Figure 6f ) . Bay- 

 onet-type setae, with shafts of the same dia- 

 meter as the spatulate setae, are also present 

 (Figure 6g) . A thoracic uncinus of the holotype 

 of C. ecaudata was figured by Hartman (1942a, 

 Figure 15g) . Other Californian material seems 

 to have uncini with slight wings (Hartman, 

 1944b, Plate 23, Figure 51) as I have observed 

 for a specimen from British Columbia (USNM 

 40304). Hartman (1942a, Figure 15f) depicted 

 two abdominal uncini from anterior segments. 

 No satisfactory view of posterior abdominal un- 

 cini was obtained from the type material. An- 

 terior and posterior abdominal uncini differ 

 in other California specimens. Anteriorly, 

 four or five rows of accessory teeth in six 

 to eight columns are situated above the ros- 

 trum ; the rostrum extends beyond the basis (cf. 

 Figure 6h; also Hartman, 1944b, Plate 23, Fig- 

 ure 50). Posteriorly, some uncini having the 

 same shape occur in the same tori with smaller 



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