BANSE: REDESCRIPTIONS OF SOME SPECIES OF CHONE AND EUCHONE 



Figure 12. — Euchone velifera new species; c-e from holotype, a, b from paratypes; 

 a-c, g not drawn to scale : a, b, ventral and left side views of anterior end of juvenile 

 specimen; c, posterior end from the left side; d, subspatulate thoracic seta; e, f, uncini 

 from fifth and 27th (sixth to last) abdominal segments. Accessory teeth schematic; g, 

 anterior end in ventral view showing staining pattern. 



high crowns and rounded, posteriorly enlarged 

 bases. 



The name refers to the sail-like wings of the 

 anal depression. 



Material studied: Type series. 



Description: The holotype is a complete, well- 

 preserved mature female of almost 3-cm total 

 length (trunk length 17 mm) and 1.5-mm width. 

 The paratypes are juveniles. In the holotype 

 the branchial crown contributes a little more 

 than one-third of the total length. The 9 or 10 

 pairs of pinnulated slender radioles are in the 

 holotype free from each other through their en- 

 tire length and have only rudimentary flanges. 

 The juveniles have a palmate membrane uniting 

 the radioles for approximately half of their 

 length. The pinnules, which are of a uniform, 

 relatively short length, are present almost to the 

 ends of the radioles so that there are only rel- 



atively short filiform free tips. A few thin naked 

 filaments are also present, the longest one being 

 about half as long as the radioles. Triangular 

 lips occur on both sides of the mouth. 



The collar (Figures 12a and 12b) is slightly 

 longer ventrally than dorsally. The dorsal gap 

 is narrow; laterally there is a small notch. Ven- 

 trally, a deep incision is formed by the collar be- 

 ing folded' inward between the two halves of the 

 branchial crown, A postsetal girdle of glands 

 encircles the second setiger. The ventral shields 

 of unstained specimens are more distinct in the 

 juveniles than in the adult animal. They are 

 indicated more by the appearance of the ventral 

 and lateral epidermis in the thorax, as contrasted 

 to that of the dorsal side, than by morphological 

 elevation (pads) on the ventrum. This is borne 

 out by staining. In the adult, very conspicuous, 

 subepidermal tissue of a creamy color is present 

 dorsally from the third setiger, having the 



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