34 IVAR ARWIDSSON, SYSTEMATIC NOTES ON SOME MALDANIDS. 



with a somewhat larger part nearer the anus and a somewhat smaller one (anteriorly) 

 downwards. There are nephridia on the 7 th — 10 th setigerous segments. 



Epidemi al glands. The cephalic plate has scattered glands on the keel and 

 just behind and at the sides of the nuchal organs; fig. 30. The inside of the borders 

 is slightly glandular. Otherwise the distribution of the glands is shown on the whole 

 by figs. 31—35. Thus the l st setigerous segment especially has a distinct glandular band 

 in front of the parapodia. On the 2 nd — 4 th setigerous segments the glands are found 

 also behind the parapodia, reaching gradually further backwards, on the 4 th segment 

 close to the posterior limit. On the 5 th setigerous segment the same posterior glands 

 decrease, though along the ventral nerve-cord they extend a good way into the other- 

 wise glandless part. On the 6 th setigerous segment behind the parapodia there are 

 glands only around the ventral nerve-cord and this to about half-way along the segment. 

 On the 7 th setigerous segment we find scattered glands behind the parapodia and, in 

 addition, a number close to the side of the ventral nerve-cord. The 8 th setigerous seg- 

 ment has scattered glands along somewhat more than half its length and here they are 

 not close to the ventral nerve-cord; there then follows a strong band of glands in front 

 of the parapodia, about similar to those on the preceding segments. It is to be noted, 

 however, that this band on the 8 th setigerous segment is of ten more or less indented 

 in its anterior edge. A median lower indentation is the most common, but there also 

 occurs, and then simultaneously, a corresponding upper one, though generally weaker. 

 In addition the anterior edge of the glandular band is often otherwise somewhat un- 

 even; the band is most frequently widest on the ventral side. When its anterior edge 

 is even all round, a groove is visible here all round or only below, which looks like the 

 limit of a segment. The posterior part — rather poor in glands — of the same segment 

 has the middle of the ventral side free from glands. There then follows in larger spe- 

 cimens the fairly even but sparsely glandular 9 th setigerous segment, where there is 

 a fine row of glands along each side of the ventral nerve-cord; similar rows of glands, 

 often somewhat stronger on the nearest segments, are then found on the following seg- 

 ments up to about the 14 th — 15 th setigerous segment, but gradually decreasing. In 

 smaller specimens a longitudinal upper median band is visible; ef. the following segment. 

 The 10 th setigerous segment is still somewhat more sparsely glandular, especially on 

 the ventral side; on the dorsal side the segment has a longitudinal band which, with a 

 certain widening at the parapodia, continues, though continuously decreasing in strength, 

 to the 14 th setigerous segment, where, however, it ends in front of the parapodia 

 and the groups of glands situated round these; on the next segment single glands (fig. 

 32) at most remind us of the same band. In front of the capillary setae of the 10 th seti- 

 gerous segment there passes off on each side a fine strip of glands (fig. 32) and similar 

 strips are more or less distinct on the next segment; on younger specimens they are 

 also seen on the 9 th setigerous segment. Besides posteriorly decreasing glands round 

 the parapodia the posterior segments have from the 10 th setigerous segment only scat- 

 tered glands, becoming fewer and fewer posteriorly. The 3 rd achaetous segment has 

 a very weak ring of glands round it, and in addition on one or both sides accumulations 

 of glands may suggest weak remains of parapodia. The three posterior achaetous seg- 



