KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 63. N:0 7. 



21 



of glands is rather weakly developed on the l st setigerous segment, but strong on the 

 following segments and on the 5 th — 7 th specially strong. On the lower side from the 2 nd — 

 3 rd setigerous segment this band is well bounded posteriorly, extending here almost 

 in a line with the uncini. On the dorsal side it is less sharply defined, especially on the 

 4 th setigerous segment; the posterior part of the 4 th — 6 fch setigerous segments, especially 

 of the two latter, has also fine and rather dense glands, while the 7 th setigerous segment 

 has at the corresponding part sparse glands, a very distinct feature and perhaps a good 

 characteristic for the species. The collar formations on the anterior segments are almost 

 free from glands on the inside; no light anterior edge without glands is to be seen, at 

 least in contracted specimens, except on the lower side of the 2 nd setigerous segment. 

 On the 4 th — 7 th setigerous segments the anterior band of glands is, however, anteriorly, 

 especially on the foremost segments, distinctly more sparse than in other parts. On 

 the 2 nd and 3 rd setigerous segments the anterior band of glands leaves the ventral nerve- 

 cord free. The glandular regions of the 8 th setigerous segment are seen in figs. 16—18; 

 the lower large glandular field shows in its hindmost part a strongly coloured band, 



i 



Text-fig. 7. Leiochone leiopygoa. — Uncinus from the 

 13 111 setigerous segment. 320: 1. 



Text-fig. 8. Leiochone leiopygos. — Part of an anterior 



capillary seta from the 13 111 setigerous segment; set a 



seen from the front. 365: 1. 



in front of which there follows a paler one, widest in the middle line. Further forward 

 on each side we notice a small glandless patch, surrounded by a zone of fairly strong 

 glands; on the back of the segment 2 strong anteriorly converging bands of glands, 

 each issuing from the posterior upper corner of the lower glandular field ( = L. johnstoni); 

 behind these oblique bands finally a larger triangulär patch of glands, the hindmost 

 part of which is most strongly glandular. The 9 th and following setigerous segments 

 have glands mainly round the parapodia and from about the 14 th setigerous segment 

 there is also a narrow ring of glands all round, increasing somewhat in width, however, 

 towards the posterior end. The l st achaetous segment has a distinct ring of glands, 

 sometimes somewhat widened at the remains of parapodia; the ring of the 2 nd or last 

 achaetous segment is narrower, especially above (ef. also fig. 19). 



Setae. The uncini of the l 8t — 3 rd setigerous segments are not specially strongly 

 changed (ef. text-fig. 6). The large tooth is as a rule long, extended and pointed; the 

 setae are rather open, but less so posteriorly, just as the point of the large tooth decreases 

 from the l st to the 3 rd setigerous segment. The lowest seta of the 3 rd setigerous segment 

 thus differs most strongly from the uppermost seta of the l st setigerous segment. None 



