FISHERY BULLETIN: VOL. 70, NO. 2 



appearance of ventral shields. The intraseg- 

 mental division of this tissue into anterior and 

 posterior sections is particularly obvious in the 

 abdomen. In contrast to shields, this material is 

 not stained by methyl green. The very large 

 wings of the anal depression are shown in Fig- 

 ure 12c. 



Each thoracic notopodium after the first seti- 

 ger contains three series of setae: about a dozen 

 limbate, about half a dozen bayonet-type setae 

 with very small wings, and 2 doz subspatulate 

 setae (Figure 12d). The thoracic hooks are of 

 the ordinary kind. An uncinus from the anterior 

 abdominal region is shown in Figure 12e; there 

 are about 8 teeth above the main fang in the 

 smaller, and about 10 teeth in the larger, hooks 

 of a torus. Uncini from the posterior regions 

 differ markedly (Figure 12f), not only because 

 of an increase of the number of teeth above the 

 main fang but also by a marked posterior en- 

 largement. There are about half a dozen ventral 

 limbate setae in each abdominal neuropodium 

 with very narrow wings. 



The color of the preserved holotype is pale 

 red-brown, except for the dorsal creamy tissue. 

 Very numerous polygonal eggs have diameters 

 up to 150 fx. The tube is clearly constructed by 

 the successive addition of rings of mucus and 

 mud. 



After using methyl green, the collar is dorsally 

 fully stained except at the anterior margin; the 

 ventral pattern is indicated in Figure 12g; the 

 patterns on the fourth and following setigers are 

 the same as those on the third. In the abdomen, 

 the intrasegmental divisions appear broader in 

 the thorax so that, owing to the fecal groove, four 

 rectangular fields of pigment per segment are 

 seen. Laterally in the thorax and abdomen, the 

 stained epidermis extends from the shields 

 around the parapodia, uniting immediately dors- 

 sal to the notopodia. Staining cells are absent 

 dorsally in the thorax but appear as faint lines 

 in the abdomen. 



The two young specimens (paratypes) are 

 about 10 mm long and 0.5 to 0.6 mm wide. The 

 approximately six pairs of radioles are almost 

 as long as the trunk and united by the palmate 

 membrane for about half their length. The col- 

 lar (Figure 12b) is not as level as in the holo- 



type. The number of abdominal setigers is dif- 

 ficult to ascertain but seems to be 27 or 28 in one, 

 with 7 setigers in the anal depression, and 29 in 

 the other specimen, with 9 setigers in the anal 

 depression. 



The smallest uncini in the third and fourth ab- 

 dominal setiger of one of the specimens were 

 very similar to Figure 12f, that of an uncinus of 

 the adult animal from the posterior segments. 

 The staining pattern is similar to that of the 

 holotype except for a lateral tongue of nonstain- 

 ing tissue which extends latero-ventrally be- 

 tween the posterior border of the collar, at the 

 level of the lateral notch, and the first para- 

 podium. 



Remarks: Euchone velifera is unique in re- 

 gard to its very deeply bilobed collar. Distinct 

 midventral incisions are also known for E. pa- 

 pilloma and E. capensis. The latter two species 

 lack laterally notched collars and very large 

 wings in the anal depression. 



ACKNOWLEDGMENTS 



It is a pleasure to acknowledge the assistance 

 and financial support by Dr. R. L. Fernald, Di- 

 rector, Friday Harbor Laboratories, and the 

 U.S. Atomic Energy Commission, Contract No. 

 AT (45-1) -1725 (ref: RLO-1725-196). Materi- 

 al was kindly lent by the 11 museums and lab- 

 oratories named on page 460. I am especially 

 indebted to the colleagues at these institutions. 

 Also, Dr. 0. Hartman, Los Angeles, allowed me 

 to describe the three new species included in this 

 paper. Dr. M. Imajima, Tokyo, gave some spec- 

 imens. Dr. M. H. Pettibone, Washington, D.C., 

 provided study space in the U.S. National Mu- 

 seum. Dr. H. L. Sanders, Woods Hole, put his 

 collection made near Friday Harbor, Wash., at 

 my disposal, and Dr. E. C. Southward, Plymouth, 

 England, lent specimens from her private col- 

 lection. Finally, Dr. D. P. Henry gave very 

 valuable advice on the preparation of the man- 

 uscript. 



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